Symbol-Based Communication Intervention for Individuals with Rett Syndrome

Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine 1690

Symbol-based communication intervention for individuals with Rett syndrome

Current practices, assessment of visual attention, and communication partner strategies

HELENA WANDIN

ACTA UNIVERSITATIS UPSALIENSIS ISSN 1651-6206 ISBN 978-91-513-1030-5 UPPSALA urn:nbn:se:uu:diva-421107 2020 Dissertation presented at Uppsala University to be publicly examined in Gunnar Johanssonsalen, (14:K120), Blåsenhus, von Kraemers allé 1A, Uppsala, Thursday, 26 November 2020 at 09:00 for the degree of Doctor of Philosophy (Faculty of Medicine). The examination will be conducted in Swedish. Faculty examiner: Associate professor Jacob Åsberg (Institute of Neuroscience and Physiology, Gothenburg University).

Abstract Wandin, H. 2020. Symbol-based communication intervention for individuals with Rett syndrome. Current practices, assessment of visual attention, and communication partner strategies. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine 1690. 59 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-513-1030-5.

Individuals with Rett syndrome need extensive support to actively participate in social interaction and to develop their communication. The overall aim of this thesis was to investigate communication intervention for individuals with Rett syndrome, especially aided symbol-based communication and partner strategies. Study I was a cross-sectional survey exploring services provided by speech language pathologists (SLPs) in Sweden. Communication aids were often used in the intervention and were found to be useful. Few SLPs used systematic tools for assessment and evaluation and communication partners were often instructed through informal conversations. In study II, a tool (AVAI) for assessing visual attention in interaction was developed and its psychometric properties were explored. AVAI was also used as an outcome measure in study III. In both studies, the tool was found to be reliable, able to detect change and acceptable to the participants. In study III, a single case experimental design was applied to evaluate an intervention consisting of aided language modelling whilst using responsive partner strategies and a gaze- controlled device. The adult participants with Rett syndrome (n=3) increased their expressive communication following individual learning patterns. The intervention was appreciated by the participants’ social network. Study IV was a case study exploring and describing a communication partner’s use of responsive and scaffolding partner strategies in interaction with individuals with Rett syndrome (n=3). The use of these strategies varied in interaction with different individuals with Rett syndrome. The communication partner responded more frequently to communication through a gaze-controlled device than unaided communication. In conclusion, gaze-controlled devices should be considered in communication intervention with individuals with Rett syndrome. Systematic tools and procedures should be applied in interventions, which is not the case in current clinical practice. Adults with Rett syndrome are able to develop their communication which highlights the need for communication support throughout their lifetime.

Keywords: aided communication, augmentative and alternative communication (AAC), assessment tools, communication intervention, eye-gaze technology, partner strategies, Rett syndrome, visual attention

Helena Wandin, Department of Public Health and Caring Sciences, Box 564, Uppsala University, SE-75122 Uppsala, Sweden.

ISSN 1651-6206 ISBN 978-91-513-1030-5 urn:nbn:se:uu:diva-421107 (http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-421107) List of Papers

This thesis is based on the following papers, which are referred to in the text by their Roman numerals.

I Wandin, H., Lindberg, P., & Sonnander, K. (2015). Communication intervention in Rett syndrome. A survey of speech language pathologists in Swedish health services. Disability and Rehabilitation, 37(15):1324-1333.

II Wandin, H., Lindberg, P., & Sonnander, K. Development of a tool to assess visual attention in Rett syndrome. A pilot study. Augmentative and Alternative Communication, 36(2):118-127

III Wandin, H., Lindberg, P., & Sonnander, K. Aided language modelling, responsive communication, and eye-gaze technology as communication intervention for adults with Rett Syndrome. Three experimental single case studies. Manuscript

IV Wandin, H., Lindberg, P., & Sonnander, K. An explorative case study of a trained communication partner’s use of responsive and scaffolding partner strategies in aided communication with adults with Rett syndrome. Manuscript.

Reprints were made with permission from the respective publishers.

Contents

Introduction...... 11 Communication and interaction ...... 11 Communication development ...... 11 Symbol-based communication ...... 12 Communication in individuals with significant communication and motor disabilities ...... 12 Rett syndrome ...... 13 Communication in Rett syndrome ...... 15 Tools to assess communication in Rett syndrome ...... 16 Communication intervention ...... 18 ICF...... 18 Communication intervention services ...... 19 Aided communication...... 20 Partner strategies in aided communication intervention ...... 21 Rett syndrome and communication intervention ...... 23 Rationale ...... 25 Aims ...... 27 The empirical studies ...... 28 Overview ...... 28 Ethical considerations ...... 28 Study I ...... 29 Participants ...... 29 Materials and procedure ...... 29 Data analysis ...... 29 Results ...... 30 Discussion ...... 31 Study II ...... 32 Participants ...... 32 Materials and procedure ...... 32 Data analysis ...... 33 Results ...... 33 Discussion ...... 34 Studies III & IV...... 34 Participants ...... 34

Materials and procedure ...... 35 Measures and data analysis study III ...... 35 Results study III...... 36 Discussion study III ...... 37 Measures and data analysis study IV ...... 37 Results study IV...... 38 Discussion study IV ...... 38 General discussion ...... 39 Intervention ...... 39 Partner strategies...... 39 Eye gaze communication ...... 40 Communication intervention for adults with Rett syndrome ...... 41 Methodological discussion ...... 41 Design...... 41 Tools and measures...... 42 Future directions...... 43 Conclusions and clinical implications ...... 43 Acknowledgements...... 45 References ...... 48

Abbreviations

AAC Augmentative and Alternative Communication ALM Aided Language Modelling AOL Alertness Observation List AVAI Assessment of Visual Attention in Interaction ESCS Early Social Communication Scales GAS Goal Attainment Scaling ICC IntraClass Correlation ICD-10-CM International Classification of Diseases, Tenth Revision, Clinical Modification ICF International Classification of Functioning, Disability and Health IPCA Inventory of Potential Communicative Acts IRA Inter-Rater Agreement, Intra-Rater Agreement MBRS Maternal Behavior Rating Scale MECP2 Methyl CpG binding protein 2 MSEL Mullen Scales of Early Learning PIMD Profound Intellectual and Multiple Disabilities RAACS Responsive Augmentative and Alternative Communication Style scale RSPS Responsive and Scaffolding Partner Strategies SCED Single Case Experimental Design SLP Speech Language Pathologist

Preface

This thesis is dedicated to people with significant motor and communication disabilities, and especially to individuals diagnosed with Rett syndrome, who all have an extensive need for communication support. They constitute a small group in society as well as in the health care system but methods and strategies are rarely developed to meet their specific needs. Interventions for individuals with other disabilities may not be suitable for individuals with Rett syndrome, or they may need to be adapted (e. g. in terms of outcome measures). This thesis also focuses, to a large extent, on adults with Rett syndrome, for whom support may be even more sparse than for younger individuals with the same diagnosis. Augmentative and alternative communication (AAC) has been an interest of mine since I started to work as a speech language pathologist (SLP) in 1994. For more than ten years, I have had the opportunity to specialise in communication in Rett syndrome and related disorders. The knowledge within this field has increased rapidly during these years. New technology, dedicated clinicians, and not least, dedicated families and interest organisations have been driving forces for the development of research and clinical expertise world- wide. In my clinical work with children and adults with Rett syndrome, I have met individuals of various ages who have benefitted from communication intervention. However, communicative development does not happen spontaneously, it requires knowledgeable, carefully planned interventions and support from close communication partners as well as professionals. The number of communication intervention studies is increasing. Nevertheless, research within the field of communication intervention for individuals with Rett syndrome is still limited. Hopefully, the studies presented in this thesis will add to the existing knowledge base. Ultimately, communication intervention research may provide individuals of all ages with Rett syndrome the best possible opportunities to actively participate in communication exchanges and to reach their full potential regarding communication and language.

Introduction

Communication and interaction Communication is a broad term that can be interpreted as a meaning-making process comprising of each communication partner’s engagement and participation in the dialogue, as well as the dialogue in itself in which the meaning is co-constructed (1). Throughout this thesis, the terms communication and interaction are used interchangeably for the exchange between two or more persons who influence each other through their actions (2). These actions can be either voluntary and intentional or involuntary and pre-intentional. This wider definition of communication as something co-constructed is used in fa- vour of a stricter definition that implies a conscious intention to share a specific message. With the wider definition, even infants or persons who do not show communicative intent can be said to communicate. Communication is also used in this thesis for each partner’s contributions to the interaction (3).

Communication development The development of communication and language begins before the child says the first words and thus uses symbols for the first time. The development occurs in three stages from being pre-intentional and pre-symbolic to intentional and symbolic (4). Each new stage entails new communication skills while the earlier skills are also still used in communication. Hence, the range and vari- ability of expressions gradually increases. Children without disabilities often move through the pre-intentional and pre-symbolic stages without external support besides regular stimulation and parenting. In the first stage, the perlocutionary stage, the communication partners infer meaning from a child’s actions. The communication is pre-intentional, i.e. the child does not direct the communication to a partner (4). In the beginning of the perlocutionary stage the child’s forms of expression consist of reflex responses or reactions to internal or external stimuli. Communication partners infer meaning from these behaviours and may often interpret them as expressions of internal states such as hunger, comfort, discomfort or pain. In the end of the perlocutionary stage, the child has developed goal-directed (voluntary) actions but does not intentionally direct these actions to influence a communication partner (5). Communication partners may interpret these actions as expressions of interest, disinterest, wants and needs, for example.

11 In the second illocutionary stage the child directs actions to the communication partner with an intention of conveying a message. The child thus ex- pects to be able to change the communication partner’s actions or perceptions with his or her own actions. Finally, in the third, locutionary stage, the child starts to use single symbols, such as words, to communicate a message (4). Communication and language development take place in a social context. Interactions with the communication partners influence the communication and language development (6, 7). For example, the vocabulary of children whose parents talk more, use a richer vocabulary, and respond contingently to their children’s expressions, has been found to be larger than when this quality interaction does not take place (8).

Symbol-based communication When children start to use symbols in the locutionary stage, this often takes the form of spoken words. A symbol “is the interpretation that a person creates for the relation that exists between a symbol and a referent” (9, p. 93). In this definition, the symbol refers, not only to the object, action or other referents, but also to the symbol-user’s interpretation of the relation. Symbols may be text, manual signs or graphic symbols. For non-speaking individuals without the motor ability to use signs, graphic symbols are the only option for com- municating language in the absence of their having learnt to read and write. Graphic symbols may be more or less abstract, i.e. more or less resemble the idea they represent (10). In this thesis, symbol-based communication refers to graphic symbols unless otherwise stated so.

Communication in individuals with significant communication and motor disabilities In this thesis, the term individuals with significant communication and motor disabilities refers to non-speaking individuals who a) do not yet use symbol communication consistently and spontaneously, and b) need assistance with mobility, and c) are unable or have severe difficulties to manipulate objects and select from an array of symbols with their hands/fingers. Co-existing conditions such as seizures are common in individuals in the group. Publications that include participants with significant communication and motor disabilities cover a wide range of participant definitions including those with complex communication needs or emergent communication, as well as those with specific diagnoses such as Rett syndrome. Much of the research on pre-symbolic and emergent symbolic communication is focused on individuals with profound intellectual and multiple disabilities (PIMD). People with PIMD may have significant communication and motor disabilities, but the latter term can

12 also refer to a wider group of individuals with a wider range of intellectual abilities. Individuals with significant communication and motor disabilities may need extensive support to develop both pre-symbolic and symbolic communication. Voluntary movements may be difficult to initiate and execute and they can also be mixed with involuntary movements which may or may not be caused by seizures. It may therefore be difficult for the communication partners to know whether their behaviours are potentially communicative (11, 12). Pre-symbolic and early symbolic development has therefore been described in more detail for individuals with disabilities who communicate pre-symboli- cally. Rowland (13) describes seven levels of early communicative development. The first two levels correspond to the perlocutionary stage. At level I, pre-intentional behaviour, the individual’s expressions consist of reflex responses or reactions to internal or external stimuli. At level II, intentional behaviour, the behaviours are goal-directed (voluntary) but the individual does not intentionally direct these actions to influence a communication partner. Levels III and IV correspond to the illocutionary stage in which the individual directs actions to the communication partner with an intention of conveying a message. At level III, unconventional communication, the individual uses behaviours that are specific to him or her and not widely recognised. At level IV, conventional communication, the individual uses gestures and vocalisations that are recognised widely in the community, such as nodding or waving. At level V, concrete symbols, the understanding and use of symbols emerge. The individual uses symbols that have a close relationship to the person, object or activity they refer to. Concrete symbols include photos and depictive signs such as “come”. At level VI, abstract symbols, the individual uses symbols with only an arbitrary relation to what is referred to and at level VII, language, the individual combines symbols. The potentially communicative behaviours in individuals with significant communication and motor disabilities are often specific to each individual and the behaviours may be subtle and difficult to recognise for communication partners (12, 14). As stated above, even when recognised, the potential communicative meaning may be difficult to interpret. Contingent responses to potentially communicative behaviours are assumed to facilitate the communicative development, for example through shaping pre-intentional (perlocutionary) behaviour into intentional (locutionary) forms of communication (12, 15).

Rett syndrome Rett syndrome is a neurodevelopmental disorder almost exclusively affecting females. The majority of cases are caused by a mutation in the MECP2-gene, a regulatory gene in the X-chromosome (16). The estimated prevalence rate is 1 per 9–10,000 females (17, 18). Rett syndrome has the code F84.2 according

13 to the International Classification of Diseases, Tenth Revision, Clinical Mod- ification (ICD-10-CM). Consensus criteria for typical (classical) and atypical (variant) Rett syndrome were developed in 2010 (19). The criteria that are required for the diagnosis of Typical Rett syndrome include complete or partial loss of acquired purposeful hand skills and acquired spoken language including babbling (19). The presentation of the syndrome is described to develop in four stages (20-22). Development of the children is seemingly typical during the first months after birth. In stage I, between about 6–18 months of age, development slows down and in stage II, occurring between 1–4 years of age, the children lose previously achieved skills. This regression (included in the criteria) can last months or years and may be very subtle (23, 24). During this regression period, the children are described as having spells of inconsol- able crying and as withdrawing from social interaction. In stage III, beginning between 2–10 years of age, the condition stabilises and the loss of functions halts. The children are usually more responsive and more inclined to engage in interaction again. However, multiple and severe symptoms and signs remain and may develop during this stage, such as dyspraxia, hand stereotypies, epileptic seizures, vacant spells, breathing dysrhythmia, fatigue/reduced alertness and heightened anxiety (22, 25). It should be noted that there is a wide clinical presentation of the syndrome (26). Apart from affecting health, these symptoms and signs also impact communication (27). Stage IV is called late motor deterioration and describes loss of or decrease in mobility. Questions regarding stage IV have been raised as the loss of ambulation may often have secondary causes and, in some cases have been possible to prevent or postpone (28). Motor functioning is generally affected in Rett syndrome. Dyspraxia, dys- tonia, ataxia and stereotypies are frequently described in literature as occurring. The dyspraxia, i.e. difficulties in performing intentional actions, is often pronounced in Rett syndrome and contributes considerably to the motor impairment (29). Urbanowicz et al. (30) observed home videos of 64 individuals with Rett syndrome and found that it took between one second and approximately four minutes for the participants to make a choice when asked. The stereotypies add to the difficulties in performing voluntary actions. Hand stereotypies are characteristic of the diagnosis and have been reported to differ from the hand stereotypies that occur in autism, for example by being continuous rather than intermittent (31). Epileptic seizures, and other types of seizures influence the responsiveness of people with Rett syndrome as well as their possibilities for expressive communication (32). Seizures may contribute to fluctuating attention. Studies examining attention in individuals with Rett syndrome have mainly involved various aspects of visual attention. Fabio et al. (33) found that participants with Rett syndrome spent less time looking at focus objects and more time looking at the caregiver’s and test leader’s faces, or at nothing at all, than a control group matched for mental age. This was interpreted as a difficulty with

14 selective attention (i.e. to attend to relevant stimuli and ignore irrelevant stimuli). These difficulties have been confirmed in other studies of visual attention (34, 35). There are also difficulties with shifting attention according to a study by Rose et al. (36). The authors found it likely that difficulty in oculomotor processes was involved. These processes “underlie the control of planned eye movements” (p. 340). In a study by Townend et al. (37), the repertoire of eye movements appeared to be the same as the control group with age matched peers. However, only half of the group could finish the procedure and a second study suggested that difficulties with selective visual attention contributed to the attrition (34).

Communication in Rett syndrome Approximately 80% of individuals diagnosed with Rett syndrome are non- speaking (38-40) although there are variants of Rett syndrome with preserved speech (19). The understanding of language is less affected than the expressive ability according to the social network of individuals with Rett syndrome. Un- derstanding of single words and situation-dependent language is reported by caretakers or observed in 50% or more of cases (32, 41-43). Individuals with Rett syndrome tend to orient towards faces and eyes rather than objects (44, 45). It is also frequently reported that people with Rett syndrome enjoy social interaction (42, 46). It should be noted that social interest, adaptive functioning and communication skills are reported to be preserved, or even improved, in adult and aging women with Rett syndrome (47-50). Research interest in early communication development in Rett syndrome has increased. In a natural history study by Neul et al. (51) of 542 individuals diagnosed with typical Rett syndrome, 53% had acquired gestures, 23% used points for wants and needs, 77% used single words, and 18% had acquired phrases before the regression stage. This suggests that individuals had reached the illocutionary phase and potentially the locutionary stage. However, there are indications that deviations from the early communication development exist (24), examples include a limited range of gestures (52), atypical cooing and babbling and that early communicative functions were not observed in some children (53). It is also frequently described that individuals with Rett syndrome were placid during infancy (54). The findings are mixed regarding communication skills post-regression. Previous studies, in which direct assessments were used, found that individuals with Rett syndrome mainly communicated pre-intentionally i.e. without directing their communication to others (41, 43). Goal-directed behaviour was observed, but no attempts to draw attention to themselves or objects were seen (43). Woodyatt & Ozanne, (55, 56) suggested that the communicative abilities were on a par with the cognitive abilities, although there were variations within the group and one of the participants demonstrated some intentional communitive behaviour, although inconsistently. It was also suggested that

15 dyspraxia may play a part in hindering communication. In more recent studies, eye-gaze technology has been used in assessments of cognitive and receptive language abilities. The findings suggest that, although the study group with Rett syndrome had lower scores compared with a group of typically developing peers, there was a wider range in abilities than previous studies have shown. Some individuals had age-adequate receptive vocabulary and language (57, 58). Regarding expressive communication, eye gaze is often reported to be the most efficient form of communication (32, 59, 60) and intense eye communication, “eye pointing”, is one of the supportive criteria for the diagnosis (19). Given that eye gaze is an important form of communication and that selective and shifting attention may be affected in Rett syndrome, it is important to further develop our understanding of visual attention in Rett syndrome.

Tools to assess communication in Rett syndrome It is widely recognised that it is difficult to formally assess abilities in people with Rett syndrome (61, 62). Approaches that have been used in research to assess communication in Rett syndrome are either (a) tasks following a relatively standardised procedure, (b) observation, or (c) information from caregivers about communication in naturally occurring situations. None of the tools or instruments used have been specifically developed to assess communication in Rett syndrome, but to assess communication in general or in individuals with disabilities. Psychometric properties are important to take into account, regardless of type of tool that is used in an assessment and reliability, validity, and utility should be considered. Reliability concerns the precision of a measurement; how consistently the measurement captures the variable of interest, such as visual attention (63). There are various aspects of reliability. For example, different observers should agree when scoring a behaviour (inter-rater reliability) and the scores should be consistent when the one observer repeatedly scores the same behaviour (intra-rater reliability). Inter-rater reliability of an observation tool is often evaluated using two coders and comparing the scoring (64), and can be established by letting one observer score the same video on different occasions and then computing kappa (65). The validity of a tool concerns how well founded the inferences that are drawn from the scores are, or in other words, what conclusions can be made based on the scores derived from using the tool (66). Tool validity assessment is a process in which several aspects are evaluated. This includes how well the measurement assesses the concept it is intended to measure rather than other concepts (construct validity) and how well the measurement distinguishes between different levels of the variable (sensitivity to change) (63, 64, 66). Yoder and Symons (64) distinguish between observing behaviours that are signs of a construct, such as a skill or a characteristic, and behaviours that are

16 target behaviours for their own sake. To assess the former “requires an infer- ence that what we are observing reflects an ability or skill we cannot directly observe” (64, p. 7). The latter are context-dependent behaviours “that are considered important for their own sake”. They are “not expected to inform us of what occurs outside of the measurement context” (64, p. 7). According to Yoder and Symons, sensitivity to change is an important aspect to examine when assessing context-dependent behaviour. Social validity refers to how important the social network considers the intervention goals, procedures and effects to be (67). The utility of a tool (i.e., its feasibility and usefulness) is rarely investigated. Feasibility can be defined as how easy and manageable the tool is to administer, while usefulness refers to how acceptable the tool is to clients and professionals as well as whether the acquired information is clinically useful (68). In two recent studies, standardised instruments have been adapted and used in gaze-controlled devices to assess reception of language and vocabulary. Clarkson et al. (58) adapted the Mullen Scales of Early Learning (MSEL), (69). The adaptations to the administration procedure included replacing standard objects with motivating objects, partial credit for multiple equivocal answers instead of full credit for one clear response, accepting swiping and tapping instead of precise movements, and eye gaze as a response method (58, p. 421). Two versions of MSEL were administered: one without eye-gaze technology (MSEL-A) and one with (MSEL-ET). The domains visual reception and receptive language were administered through eye-gaze technology, although not all of the items were considered suitable for adaptation and thus not used. The scores were similar, but the time for administration of MSEL- ET was shorter. Compared with results from the interview tool Vineland Adaptive Behavior Scales-Second Edition (70), the scores from the adapted MSEL were higher and displayed a wider range. These results should be viewed in the light of the methodological limitations including difficulties in comparing the adapted versions with each other and with the standardised MSEL. Even so, the results are interesting and indicate that the adapted MSEL is a potential option for assessing developmental domains, including receptive language. Ahonniska Assa et al. (57) adapted the Peabody Picture Vocabulary test to assess receptive vocabulary. The responses were given through eye- gaze technology and each response was then confirmed by asking the participant to confirm through a yes/no-response. Psychometric properties of this adaptation were not reported. The Early Social Communication Scales (ESCS) (71, 72) uses play with objects and is administered with minimal verbal interaction during communication bids. It was used to compare a group of girls with Rett syndrome with a control group (33). ESCS has been used in numerous studies with conditions other than Rett syndrome and reliability is reported to be above the acceptable level. In Fabio et al (33) the inter-rater reliability was computed by the ratio

17 of agreements of number of categories of each type (87%). Given the difficulties that individuals with Rett syndrome have in manipulating objects and that interest in objects appears to be limited, ESCS may not be best suited for assessing communication in Rett syndrome. Communication Matrix (13, 73) is a tool used to assess communicative form and function. The assessment can be based on observations or interviews. Grether et al. (74) compiled parent interviews from clinical assessments according to Communication Matrix. Communication Matrix was reported to have high inter-rater agreement (73) and construct validity was estimated to be high by experts (75). The Inventory of Potential Communicative Acts (IPCA) (12) was developed to identify potential communicative actions and its instructions are relatively open (15), which can cause problems regarding reliability and validity. The tool has been used to describe form and functions in studies describing communication in Rett syndrome (53, 59). Point-by-point inter-rater agreement was reported as 87% in one of these studies (53). In a field test, interview data was compared with observation data and the communication acts described by parents were also observed, which strengthens the validity of the IPCA (12). Goal Attainment Scaling (GAS) (76) was used to evaluate an intervention in which gaze-controlled devices were implemented. GAS is used in clinical practice to assess individualised longitudinal goals and has also been used in research studies. Possibly due to its flexibility, the tool’s reliability and construct validity have been difficult to establish. Social validity may be one of the most important aspects of validity of the tool according to Schlosser (77). Many of the tools measure changes in complexity and may not be sensitive enough to detect small changes or when an individual uses the same type of communication behaviour but more frequently. Moreover, ESCS and Com- munication Matrix, are norm referenced and based on typical communication development in which intentional communicative actions are important. The operationalisation of those actions often requires a sequence of movements or that the coder interprets the intention which is a recognised difficulty in Rett syndrome. For instance, in Communication Matrix, the observer or informant interprets the level of intentionality in the child’s actions (13) which is not easily done in Rett syndrome.

Communication intervention ICF The International Classification of Functioning, Disability and Health (ICF) is a classification of health and health-related conditions that was developed by the World Health Organization (WHO) and published in 2001 (78). It is a

18 framework describing functioning and disability and the interplay between individual factors and environmental (contextual) factors. ICF distinguishes between body functioning and structures, activity, and participation.

Figure 1. The ICF model of disability

Body functioning and structures are the physiological functions including psy- chological functions and anatomical parts. Activity refers to the execution of a task or action by the individual while participation refers to the individual’s involvement in everyday situations and in society. Environmental factors can serve as facilitators or barriers to an individual’s functioning and include context, products and technology, knowledge and attitudes of the communication partners, social support and relationships. Several of these factors are included in the support provided by the habilitation services in Sweden. Personal factors comprise features that are not part of the primary health condition such as gender and age and also factors such as an individual’s attitudes towards social interaction, for example. ICF highlights the importance of participation which means that in addition to assessing, teaching and training how an individual performs a task, it is also necessary to implement these tasks in naturally occurring situations. It also important to optimise the individual’s engagement in various situations in daily life. Participation is influenced by many factors and may therefore be increased by changes in environmental factors alone.

Communication intervention services In Sweden, communication assessments and provision of communication aids are often provided through the region health care system, often by teams within the habilitation services. Implementation and day-to-day support often

19 take place at pre-school, schools or daily activity centres organised by the lo- cal municipality. Individuals with significant communication and motor disabilities are also entitled to personal assistance, thus personal assistants support the daily communication and use of communication aids. However, parents of individuals with disabilities report that they need to take an active role in finding information and services (79). Parents also report that they need to coordinate and monitor their children’s personal assistance for them to receive the best, possible support (80). In many countries speech and language pathologists (SLPs) have a central role in communication intervention services. In Sweden, the SLPs that provide services to people with Rett syndrome are frequently part of teams supporting people with a wide range of disabilities. Some SLPs work in teams specialis- ing in aided communication or communication devices that serve a county or a larger region. Assistive technology provision has been found to differ between region health authorities in Sweden (81, 82). Internationally, pre-service education, practice and the formal organisation of SLPs working with communication interventions also vary. There are also indications that people with communication disabilities do not get access to aided communication even when needed (83-85). Parents and others in the social network of non- speaking individuals report a lack of support in choosing and implementing communication aids (86-89). An investigation of the current provision of communication intervention services by the Swedish health sector to individuals with Rett syndrome could indicate the direction for further studies.

Aided communication There is strong evidence that augmentative and alternative communication (AAC) including communication aids facilitate communication and communicative development for non-speaking individuals (90-93). Reported outcomes include increased use of a range of communicative functions, (such as requesting, protesting, commenting and choice-making), reduced rate of chal- lenging behaviours, increased receptive and expressive vocabulary and increased use of speech (91). AAC includes unaided forms when no external tools are used and aided forms when such tools are used (91). Examples of unaided AAC include facial expressions, body movements, gesture and signs, visual behaviour and vocalisations (73). Aided forms of AAC can be low tech or high tech. Low-tech communication aids do not have any electronic com- ponents and examples include symbol cards, communication boards or communication books with photos, graphic symbols or text. High-tech communication aids are electronic devices or computers ranging from buttons with one single message to gaze-controlled computers. Aided forms of AAC often use graphic symbols that may have varying degrees of iconicity, i.e. similarity to the concept they represent (9). The collection of symbols (vocabulary) can be arranged in different types of displays or boards, including activity boards

20 with symbols that are used in a specific activity and core boards with symbols that may be used in many situations throughout the day. When introducing aided communication, individuals with significant communication and motor disabilities need alternative access methods to select the symbols. With gaze-controlled devices, individuals can select symbols on the screen of the device by focusing their gaze and holding it for a certain amount of time (i.e. dwell time), by blinking or by using an external switch (94). For low-tech communication aids, partner-assisted scanning, (i.e. when the communication partner reads out the options and the individual selects the wanted option by giving a “yes-signal”) may be an option (95, 96).

Visual attention An individual’s attention and alertness are important for all learning. Visual attention is presumed to be important for the learning of spoken language. Children tend to look at the hand and the object when their parents gesture towards the objects (97, 98). Language learning is assumingly facilitated when the parent simultaneously labels the object. Visual attention is potentially even more important in learning graphic symbol-based communication. To connect the graphic symbol to the spoken word, and/or the referent, the individual needs at minimum to focus the gaze at the symbol. Aided communication thus differs from unaided communication by adding a gaze focus. Instead of shifting the gaze between the communication partner and the object of attention, the individual needs to shift their gaze between the communication partner, the object of attention and the symbols (99). Visual attention in relation to symbol-based communication aids has mainly been assessed in laboratory settings. These studies have largely focused on how AAC displays are processed, and the best way to arrange and individualise the displays (100) while no tools have been found for the assessment of visual attention in interaction.

Partner strategies in aided communication intervention Numerous papers have acknowledged that the communication partners are important as informants in assessment and implementation of aided communication (101-103). Partner strategies are intervention strategies that are used by the communication partner to support communication and communicative development (101). Systematic instruction has been identified as important for a positive outcome in aided communication intervention (101, 104). Methods and programs for instructing the communication partners have been developed and evaluated (105) including programs and strategies for communication partners of individuals with significant communication and motor disabilities. Rensfeldt Flink et al. (106) examined the experiences of parents of children with PIMD after a communication course. These courses are often offered through habilitation services in Sweden and are aimed at introducing and teaching parents various partner strategies, including responsive strategies and

21 use of multi-modal AAC, such as manual signs, single message devices, and aided symbol-based communication. The parents emphasized that they used responsive partner strategies more often after the course, and particularly that they more often gave their child time to communicate and paid attention to, and acknowledged, the child’s behaviour. The results regarding AAC were more mixed with parents finding AAC “difficult to apply with the child” or “too soon” (p. 8). The authors state that research regarding how different factors affect parents’ use of AAC is warranted. Two strategies that are gaining evidence as symbol-based aided communication intervention are responsive strategies and aided language modelling (ALM). Responsive strategies and ALM are both used in naturalistic interactions, rather than in highly structured tasks. Previous research show children’s communicative and linguistic development correlate with a responsive communicative style in parents or other communication partners (107-109). Examples of responsive communication include giving time for responses, looking for potential communicative actions and responding accordingly (110). Although researchers seem to agree that responsivity refers to contingent responses, measures and studies that investigate responsive strategies often include other strategies that are thought to have a positive impact on development such as labelling and expanding on the child’s actions and utterances (110-112). These packages include strategies that both precede and follow on the individual’s communicative behaviour and with slightly different purposes. The bundle of strategies is used to create a communicative environment that is generally advantageous for communication participation and development (113). In sum, the use of responsivity as a term varies widely both in term of what strategies that are included, how these are categorized and what strategies they are combined with. Several studies show that responsive parent strategies facilitate social and communication development in children with disabilities (114-116), for example autism (117, 118), Down syndrome (119) and intellectual disabilities (120, 121). A small number of studies have specifically explored responsivity in interaction between a communication partner and individuals with significant communication and motor challenges (122-124). Parents to individuals with significant communication and motor disabilities were responsive (122) and their responsivity may increase through intervention. (106). There are few observational studies examining the use of responsive strategies in aided interactions with individuals with disabilities. Medeiros et al. (125) did not find any differences in responsivity when parents and their children played with familiar or unfamiliar toys, and no difference was found regardless of whether single-message speech-generating devices were used or not. This was also the finding in a study that examined parents’ use of responsive strategies in different play activities (126). No studies could be found in which symbol-based communication was used. Most studies have examined parent responsivity but it also seems to be beneficial for engagement and language when teachers have

22 a responsive communication style (107, 127). It is not established whether personal and contextual factors influence the use of responsive strategies. The Maternal Behavior Rating Scale (MBRS), (111, 112) has been used to investigate interaction between parents and individuals with significant motor and communication disabilities (114, 122, 123, 128, 129). The MBRS com- prises 12 items categorised into four factors of which one is labelled “responsive”; responsive/child oriented, affect/animation, achievement orientation and directive. MBRS was not specifically developed for communication development and does not specifically take aided interactions into account. The Responsive Augmentative and Alternative Communication Style scale (RAACS) (110) was developed for assessing parents’ communicative styles with children with communication difficulties. The scale covers use of responsive partner behaviours that have been identified as important in AAC literature and care was taken to ensure the procedure was ecologically valid. The scale was tested for reliability and validity and, after adjustment, deemed to be reliable, feasible and have excellent internal consistency (110, 130). Aided language modelling (ALM), i.e. when the communication partner uses symbols in a communication aid when speaking is often used in combi- nation with responsive strategies. The rationale behind ALM is to provide models for communication that the non-speaking individual may be able to use. ALM may therefore be used before the individual necessarily uses symbols to express themselves. Communication interventions involving ALM have been shown to have positive outcomes for individuals of various ages and developmental stages (131, 132). ALM has also been shown to have positive effects on a range of language skills. These include: pragmatic skills such as turn-taking (133, 134); expressive and receptive vocabulary (135-138); and grammar (139-141). Despite the growing support for ALM, few replications have been conducted and participants, measures and procedures vary across studies. Most studies of ALM have targeted individuals who were able to access symbols by pointing and several of the participants also used gestures to communicate (136, 138, 142, 143). Only one individual who used alternative symbol selection methods has participated in a study investigating ALM. (144) and no study included participants with Rett syndrome.

Rett syndrome and communication intervention Knowledge and practices in the AAC field are developing quickly (145, 146) and the number of communication intervention studies involving individuals with Rett syndrome have increased in the latest decade (147). Recently, consensus-based guidelines regarding communication intervention have been published to support clinical decisions (27, 96). The guidelines were developed in three phases: literature review, survey of experiences of families and clinicians, and a two-stage Delphi survey including a panel of experts consist-

23 ing of expert clinicians and representatives of parent organisations. The guidelines consist of a table with over 250 statements and recommendations that reached consensus, a handbook in which the statements and recommendations are explained and illustrated by examples, and a publication describing the methodology. The guidelines include parts that are specific to Rett syndrome (i.e. features and characteristics of Rett syndrome and their impact on communication and a focus on communication through eye gaze). Other parts are more general and could potentially be applicable for individuals with other conditions. The guidelines include a range of intervention strategies (e.g. responsive strategies and ALM) and also emphasize the importance of introducing a symbol-based communication aid that includes a larger selection of symbols to optimise communication and language development. Although the guidelines were systematically developed, they draw on a small number of publications on Rett syndrome, evidence from studies including other populations and clinical and family experiences. As with all guidelines, these consensus-based guidelines need to be reviewed and updated as the research-based knowledge expands. Communication aids seem to be a promising way to elicit more specific and intentional communicative acts. People with Rett syndrome can learn to touch or look at pictures on instruction, demonstrate literacy skills, as well as to choose, request and comment when given systematic instruction and access to communication aids (135, 148-160). However, these studies predominantly have targeted a limited number of communicative functions. The studies also often have targeted early communicative functions such as requesting or choice-making rather than communicative functions that facilitate ongoing interaction. In most of the studies a therapist provided the interventions. Few of the aforementioned studies included a more extensive vocabulary for a variety of settings.

24 Rationale

Rett syndrome is a rare disorder and some of the symptoms and characteristics that impede communication are syndrome specific. Communication aids have been found to elicit more intentional and specific expressive communication in individuals with Rett syndrome. Nevertheless, those involved with Rett syndrome report a need for support in choosing and implementing communication aids and knowledge and practice vary across individual therapists and regions around the world. A lack of communication support services may lead to the abandonment of communication aids even though they could still be beneficial for the non-speaking individual. Individuals with significant communication and motor disabilities, including those with Rett syndrome, form a small proportion of the group supported by habilitation services in Sweden. Existing assessment tools and intervention formats and strategies may therefore not meet the needs of these individuals. Knowledge of the current communication intervention services provided to people with Rett syndrome in Sweden is limited. It would therefore be valuable to investigate the current situation to identify gaps and draw from experiences collected. Visual attention is central to communication through eye gaze, which is the most important form of communication for many individuals with Rett syndrome. Visual attention is important for learning symbol-based communication. There is currently no tool for assessing visual attention during interactions. Such a tool could be useful in planning and evaluating symbol-based aided interventions. Overall, there is a paucity of assessment tools that are suitable for evaluating interventions for individuals with Rett syndrome. It is also necessary to systematically explore intervention strategies for individuals with Rett syndrome that are knowledge-based for other groups. Aided language modelling (ALM) is a strategy that has been found to increase symbol-based expressive communication in non-speaking individuals. No such intervention study has been conducted with participants with Rett syndrome, and the research that includes individuals who use alternative access is sparse. ALM is often used in conjunction with other strategies such as responsive communication partner strategies. Responsive partner strategies have been found to facilitate communicative development in several studies. However, responsive partner strategies have been described and assessed dif- ferently in various studies and little is known about the detailed mechanisms. For example, it is not yet known whether factors related to the non-speaking individual or his/her context may influence the communication partner’s use

25 of these strategies. Moreover, research on responsive strategies in aided symbol-based interactions with individuals with significant communication and motor disabilities is lacking. In summary, although communication intervention research is quickly growing, there is still a need for knowledge regarding tools and intervention strategies to optimise communication and language development.

26 Aims

Study I: To explore the service provided to people with Rett syndrome by Swedish speech language pathologists working in various habilitation settings. Specific research questions were: Which intervention methods are used to assess and evaluate communication in Rett syndrome? What are the overall aims, formats and estimated outcomes of general communication interventions for people with Rett syndrome? What are the formats and estimated outcome of communication?

Study II: To (a) develop a tool for assessing visual attention in individuals with Rett syndrome using augmentative and alternative communication with a communication partner during naturalistic interactions in clinical settings, and (b) explore aspects of the tool’s reliability, validity, and utility. This includes an assessment of (i) inter- and intra-rater agreement, (ii) sensitivity to change, and (iii) acceptability.

Study III: To examine the effect of a communication intervention package on expressive communication and visual attention in individuals diagnosed with Rett syndrome. More specifically, the aims were to examine the effect of aided language modelling while using responsive partner strategies and a gaze-controlled device, on the participants’ rate of digitised words per minute, different digitised words per minute, and visual attention.

Study IV: To explore and describe a trained communication partner’s use of Responsive and Scaffolding Partner Strategies (RSPS) in interactions with adults with Rett syndrome. More specifically, the study aimed to explore whether the use of RSPS varied as measured through the Responsive Aug- mentative and Alternative Communication Style scale (RAACS), (a) in interactions with different participants, and (b) when the communication partner also used aided language modelling, and (c) whether the rate of confirmations and expansions differed between the participants’ digitised and non-digitised communication.

27 The empirical studies

Overview

Table 1. Study design, participants, data collection and statistical methods Study Design Participants Data collection Statistical methods I Cross-sectional SLPs (n=77) Web-based Descriptive study survey statistics

II Descriptive psy- Teenagers & Video-recorded Descriptive statis- chometric study adults (n=11) interactions tics, Cohens kappa, Wilcoxon signed rank test

III Single case Adults (n=3) Video-recorded Descriptive statis- experimental interactions tics, Tau-U, Intra- design Class Correlation

IV Case study AAC specialist Video-recorded Descriptive statis- Adults (n=3) interactions tics, Wilcoxon signed rank test, Friedmann test

Ethical considerations Ethical regulations and guidelines were followed according to the Declaration of Helsinki and complied with Swedish law. According to Swedish law, ethical approval was not sought for study I since no sensitive data was collected and individual responses could not be traced back to any specific e-mail address. The participants received written information about the study through e-mail, in which they were told that participation was voluntary and that their answers could not be linked to any specific e-mail address. The e-mail also contained a link through which the SLPs could remove themselves from the distribution list. Studies II-IV obtained ethical approval from the Regional Ethical Review Board (Dnr 2014/222 & Dnr 2018/079). The caregivers or trustees were given written information about the confidentiality of the study and gave their written informed consent on behalf of the participants. The

28 caregivers and trustees were informed that they were free to withdraw on behalf of the participants at any stage without any adverse consequences. In study II, the participants with Rett syndrome were also shown a schedule with text and photos explaining what would happen during the data collection. Be- fore each session the communication partner showed the same schedule and explained what would happen. The participant could then give consent by participating or not. The caregivers were present during the data collection in studies II-IV and were instructed to alert the test leaders to any signs of discomfort inflicted by the situation on the participants with Rett syndrome. The test leaders were also attentive to signs of discomfort from the participants with Rett syndrome. In such cases, the activity was changed or the session would be terminated.

Study I Study I was a web-based survey with a cross-sectional descriptive approach.

Participants Seventy-seven speech language pathologists (SLPs), working in Swedish habilitation centres and technical aid centres, participated in the survey.

Materials and procedure A study-specific web-based survey was used (Appendix 1). The survey consisted of four sections, covering; (a) demographics and work task-related data, (b) aided communication intervention in general, (c) background data on the person with Rett syndrome, time frames and aims of the intervention, format and outcome of general communication intervention, and (d) aided communication intervention. The survey was administered through the survey tool Sur- veyMonkey (161). A manual search of the web pages of Sweden’s different county council’s web pages was conducted to identify the e-mail addresses of SLPs working at habilitation and technical aid centres. These SLPs were asked to provide e- mail addresses to any additional SLPs that were missing from the distribution list. A cover letter with information about the study and a link to the web- based survey was sent to the SLPs on the final distribution list (n=352). Two reminders were sent.

Data analysis Descriptive statistics were used to present the data as frequencies and percent- ages.

29 Results Of the 352 SLPs invited, 256 (67%) responded. Of these, 77 SLPs worked with aided communication and had experience of working with at least one individual with Rett syndrome and could therefore participate in the study. The majority (48%) of the participants had experience of working with only one client with Rett syndrome. Information from the social network of the individual with Rett syndrome and observation were the most common approaches to assessment, followed by direct interaction. Systematic instruments and tools were not used in 65% of the assessments. Generally, interventions mostly targeted communicative functions that express wants and needs (choice making and requesting). Just over a quarter of the SLPs targeted communicative functions that are important in interaction (turn-taking and joint attention). About half of the SLPs did not target more linguistically charged communicative functions (asking, commenting, narrating, and initiating topic) at all. Partner strategies were targeted in all interventions. The number of SLPs who targeted each partner strategy “exclusively” or “to a large extent” is presented below: • Behaviour state regulation: “Catch attention, regulate arousal”, n=36 (47%%) and “identify motivating activities”, n=51 (67%). • Responsive strategies: “Acknowledge and confirm expressions”, n=52 (68%), “attend to expressions”, n=46 (61%), and “give time”, n=48 (63%). • Eliciting specific actions: “Expectant delays”, n=38 (50%), “model communication”, n=36 (47), and “provide opportunities for choice making”, n=54 (71%).

Partner strategies were exclusively, or to a large extent, instructed informally in conversation. Communication aids were reportedly used by 87% of the respondents, and 94% of them included trials with two or more communication aids. Communication aids that aimed to support understanding (pictures/objects of reference and visual support) and single message devices were most commonly used, closely followed by communication charts/books. Thirty- eight percent of the respondents included gaze-controlled computers in interventions and 25% included computers with other access options. Gaze was used as an access method in 77% of interventions and hand or one or more fingers were used in 45% of the interventions. Of the communication aids used, 60-90% were reported to be useful by the SLPs with the exception of computers with other access than eye gaze (47%) and the Picture Exchange Communication System (PECS) (44%). Most SLPs reported that the aids clar- ified or increased the client’s communicative contributions. They considered that their client contributed to communication more frequently or effectively through communication aids ranging from choice-making (73%) to narrating (8%). The results showed that the communication aids were used in at least

30 one setting as reported by half of the survey respondents. One third of the SLPs reported that the aids often/always worked satisfactorily according to the social network of the client.

Discussion The clients’ social networks were highly involved as informants in assessment and evaluation. Observations in settings that were well-known to the individuals and in interaction with familiar communication partners were also common assessment and evaluation procedures. Both of these practices are considered important by researchers (162-164). Systematic instruments and tools were rarely used, although some tools of potential clinical value exist, such as Inventory of Potential Communication Acts (IPCA) (12). The communicative functions choice-making and requesting were most frequently targeted which is in line with a study by Von Tetzchner et al. (1997) (43). Turn-taking and joint attention, which are important in interaction, were not frequently targeted. However, the use of communication aids was considered to positively influence these functions, which are considered to be foun- dational for communicative development (165-167). Communicative functions that are used in conversation, (e.g. commenting) were not commonly targeted. In one study, girls with Rett syndrome commented and labelled more frequently when communication aids were introduced in story book reading (135). The communication partners were most often instructed in informal conversations, which has also been reported in other populations (168). However, previous studies have suggested that systematic and strategic instruction may increase the likelihood that the partner strategies are used and generalised on a long-term basis (104). The majority of the SLPs included communication aids in their intervention and deemed that they worked well and were used in at least one setting. Two previous studies surveying parents of individuals with Rett syndrome report somewhat differing results. In Didden et al (59), none of the girls used communication aids to express themselves according to their parents while one third of the children and adults used communication aids in a previous Swe- dish study (39). This may reflect differences in forms of expression. However, the methodology in these studies differed from each other and from the current study, and the differences should be viewed in this light. In line with previous research, (43, 169, 170), less complex communication aids (pictures for reference and single-message devices) were used most frequently. Nevertheless, gaze-controlled devices, despite being more complex, were considered useful. In a study by Calculator (168), parents of individuals with Angelman syndrome also reported that more complex communication aids worked well, partly because they enabled their children to use a more extensive vocabulary.

31 One limitation of the study was the risk of recall bias even though many of the respondents reported that their latest contact was within the preceding 12 months. Caution should be taken when interpreting results as the results from the survey are not supported by observational data or reports from every day interaction partners. Nevertheless, it may be concluded that the AAC process was not supported by the use of tools and that all parts of the intervention process did not follow research-based knowledge.

Study II Study II consisted of two phases. In Phase 1, the tool Assessment of Visual Attention in Interaction was developed. In Phase 2, the revised tool’s reliability and aspects of validity was assessed using video-recorded interactions with a group of participants with Rett syndrome.

Participants Two individuals with Rett syndrome participated in the video-recorded interactions during Phase 1 and nine individuals with Rett syndrome participated in the video-recorded interactions during Phase 2. Three external coders participated in Phase 1 and one of these also participated in Phase 2 during the assessment of inter-rater reliability. All coders had a wide experience of assessing communication with individuals with communication and motor disabilities.

Materials and procedure A Panasonic HCx920 video camera was used to record video clips of interactions for both phases and Adobe Premiere Pro CC3 video editing software was used to code the recorded interactions. A symbol set Picture Communication Symbols was arranged in pages for core words (e.g. more and finished), for comments (e.g. good and boring), and for specific activities (e.g. sing and play). For Phase 1, a preliminary version of the Assessment of Visual Attention in Interaction (AVAI) tool was used. The first 5 minutes of four video-recorded interactions were independently coded by three coders using the preliminary version of AVAI. They also noted comments on the coding process while coding. The first author conducted a brief interview with each of the coders once the coding was complete in order to explore feasibility. Inter-rater agreement was assessed across all three coders. For Phase 2, the revised version of the AVAI tool was used, consisting of instructions for the video-recorded interaction, definitions of coding categories and the coding procedure. The instructions were that the video-recorded

32 interactions should take place at a table during activities that were considered interesting to the participant. A symbol set and objects used in the activity were to be placed within the field of vision. When interacting, the communication partner was to engage the participant in the activity, give opportunities to choose and wait for initiative. The first step in the coding procedure was to identify what clips to code. For this, the video-recorded session was coded using the Alertness Observation List (AOL) (171) to identify the four minutes where the participant was the most alert and focused on the environment. The next step was to identify gaze shifts in the four-minute clip. Each gaze shift was noted along with the gaze focus (communication partner, object, symbol set or no specific focus). In the last step, all focused gazes (one second or longer) were identified by calculating the time between each gaze shift. In Phase 2, two interactions with each participant were video-recorded (in total 18), and to explore sensitivity of change, the communication partner used aided language modelling (ALM) in one of these interactions. The first author coded all clips.

Data analysis In Phase 1, occurrence percentage agreement across all three coders was calculated and the comments were grouped. In Phase 2, six of the 18 clips were coded by the external coder to assess inter-rater agreement and the same coder coded six randomly selected clips to assess intra-rater agreement. Cohen’s kappa was used to assess inter-rater and intra-rater agreement. Acceptability was studied with the AOL assessments and presented with descriptive statistics. A Wilcoxon-signed rank test was used to analyse the differences between focused gazes when ALM was used and when it was not used. SPSS version 22.0 was used for all analyses.

Results Phase 1 resulted in a revised version of the AVAI tool. The revisions included that the Alertness Observation List (AOL) was added to identify what se- quences to code and that visual attention was operationalised as focused gazes. In Phase 2, the participants were assessed using AOL as being active/focused on the environment for between 6 to 98% of the coded intervals and agi- tated/discontent for 1% of the coded intervals. The number of focused gazes were 0-22 for communication partner, 1-15 for objects, and 0-13 for symbol set. The total number of gazes ranged between 7 and 45. Inter-rater agreement was moderate for objects (0.79) and strong for communication partner (0.86) and symbol set (0.88). Intra-rater agreement was strong for communication partner (0.95), objects (0.81) and symbol set (0.93). For the whole group, there were 24 more focused gazes at the communication partner when ALM was used, 15 at objects, 26 at the symbol set, and 81 in total. These differences

33 were significant for gazes at the symbol set and for the total number of focused gazes.

Discussion Visual attention is an important aspect to assess in aided AAC interventions, especially for individuals with Rett syndrome for whom eye gaze is considered to be the most frequent form of communication. The AVAI tool developed and used in this pilot study appears to be the first tool to assess visual attention in interaction. It has the potential to be useful both in research and clinical practice. The reliability was acceptable although measures can be taken to enhance it even further. The tool appeared to be acceptable to the participants and be valid in terms of sensitivity to change. The step-by-step procedure applied in this pilot study was important for the tool’s development to enhance reliability and feasibility, although there is still room for development. Clinical acceptability and feasibility remain to be examined.

Studies III & IV In study III, a modified withdrawal (A-B1-A1-B2-A2) single case experimental design with a direct inter-subject replication across three participants was applied. All sessions were video recorded. In study IV, the recorded interactions from the first two phases were analysed. The participants, material and procedure are therefore described together for these two studies.

Participants Three women diagnosed with Rett syndrome participated in the study. The interventionist (communication partner) was an AAC educational specialist, trained and experienced in responsive partner strategies and aided language modelling (ALM). Participant 1 was 31 years old and communicated through body movements, visual behaviour and relatively consistently a yes/no signal. She also used photos, objects or abstract symbols to request, choose and to comment. She was reported and observed to have difficulties with her oculomotor control. Participant 2 was 27 years old and used facial expressions, body movements, visual behaviour and looked at symbols for yes/no. She also used photos, objects or abstract symbols to request, choose or name things and activities. Participant 3 was 29 years old and communicated through body movements, simple hand gestures, sounds and facial expressions. She used photos and a few abstract symbols for choice making, and in a few situations to comment.

34 Materials and procedure The sessions took place at a specialist AAC centre in a room with few com- peting stimuli. The interventionist interacted in activities that were judged by the caregivers to be motivating for the participants. Over a six-week period, 32 sessions were conducted with each participant. The baseline phase (A) comprised of six sessions, each intervention phase (B1 and B2) comprised of eight sessions and the withdrawal phases (A1 and A2) comprised of five sessions. Two sessions were conducted on the same study day to limit the number of journeys to the centre for the participants. The sessions lasted between 15 and 41 minutes. A vocabulary consisting of pages with core words, comments, and activity specific pages was programmed into a gaze-controlled device (Tobii I12+) using the software Communicator. The participants’ own favourite books and games were used in the activities as well as games, books, and a tablet with apps, music, and video clips regularly used in assessments at the centre. The sessions were recorded with a Panasonic HCx9201 video camera and a Sony HC22E video camera. The video editing software Adobe Premiere Pro CC3 was used when coding the recorded interactions. During the baseline phase the interventionist used responsive partner strategies, the gaze-controlled device was placed on the table within the field of vision of the participant and was accessible, although slightly to the side. The dwell time (the time period the user has to focus their gaze to activate a choice on the screen) was set at one second. In the intervention phases, the following changes were made: the interventionist pointed at symbols on the screen while speaking (using ALM) and an individual dwell time was set. During the withdrawal phases (A1 and A2) the interventionist did not use ALM but the individual dwell time remained and the interventionist continued to use responsive strategies. Before the baseline session, the gaze-controlled device was calibrated and a training page-set was used to check that the participants could access all the symbols on the screen. The individualised dwell time was estimated based on this session. The caregivers were also interviewed using Communication Ma- trix to obtain background information and information on indications of different levels of health status was also collected. These descriptions were used when the caregivers estimated general health at the beginning of each study day. After the last session the first author conducted an informal interview with the caregivers to explore social validity of the procedure and intervention.

Measures and data analysis study III Rate of digitised words per minute: The number of words expressed through the gaze-controlled device by the participant was counted. Repetitions of a

35 word within four seconds and without gaze-shifts in between were not counted. The total rate was divided by minutes of the session. Rate of different digitised words per minute: The number of different digitised words was counted and the total rate was divided by minutes of the session. Visual attention: The tool that was developed in study II, AVAI was used to assess visual attention. The total rate of focused gazes was calculated. The data was analysed following the procedure described in Lane and Gast (172). The effect size was calculated using the Tau-U calculator available on the website singlecaseresearch.org. An external coder coded 21 (22%) clips selected through stratified random sampling. Cohen’s kappa was used to assess inter-rater agreement (IRA) for digitised words and different digitised words, and IntraClass Correlation (ICC) was used to assess IRA for visual attention. A two-way mixed model, single-rater and absolute agreement ICC was used. The significance level was set at p < .001. All IRA analyses were performed using SPSS version 25.0.

Results study III For the graphed results and the Tau-U results, see Figures 2-10 and Table 2 respectively in the original manuscript. Few trends were stable and across the participants there was a pattern of a lower rate every other session. Rate of digitised words per minute: For Participants 1 and 2, visual inspection did not reveal any intervention effect across all phases. The overall effect size was moderate. A clear increase could be seen in the first intervention phase and the effect size was large. No clear withdrawal effect could be seen. For Participant 3, visual inspection showed no intervention effect. Rate of different digitised words per minute: An intervention effect across the phases could be seen for all participants. The overall effect size was large across all participants. Rate of focused gazes: An intervention effect was demonstrated for Partic- ipant 1. The overall effect size was large. For Participants 2 and 3, no intervention effects were demonstrated through visual analysis. The overall effect sizes were moderate. Additional results: All caregivers reported that the participants had appeared to enjoy the intervention. They were perceived to be in a good mood and the caregivers of Participants 1 and 2 reported that they had learned strategies simply by observing the interventionist during the sessions with the participants and that they had used the gaze-controlled device more frequently at home in conversations with the participants after the study sessions. Treatment fidelity: In 25% of the sessions, the rate of ALM did not reach two models per minute. The RAACS score was above the pre-set threshold during all sessions. Inter-rater agreement was 0.91 for digitised words, 0.99

36 for different digitised words, and 0.78-0.90 for visual attention (focused gazes).

Discussion study III All three participants increased their rate of expressive communication in at least one aspect. Two of the participants increased their rate of digitised words per minute but no withdrawal effect could be demonstrated. ALM may thus only partly have contributed to the increased rate. Moreover, the rate of digitised words may not be a reversible variable. For one participant, the intervention did not have any effect. This participant’s communication profile slightly differed from the others. An intervention effect was demonstrated on the rate of different digitised words across the participants. This is not surprising as ALM included the interventionist changing pages and thus provided access to a more varied vocabulary and may also have drawn attention to vocabulary relevant to the activity or topic. ALM had an intervention effect on visual attention for the participant with the most severe observed oculomotor difficulties. The detailed observational measures may provide clinically valuable in- sights. The design of study II does not allow the results to be generalised to individuals outside of the study group. Nonetheless, the results of the study highlight the need for intervention options for adults with Rett syndrome as well as the need for further communication intervention studies.

Measures and data analysis study IV The tool Responsive Augmentative and Alternative Communication Style scale (RAACS) (110) was originally developed to assess parents’ communicative style based on video recordings of dyadic interaction. It was adapted for the study to suit its specific conditions and also following the recommendations from earlier studies. The first ten minutes of the session were coded. The communication partner’s use of strategies was rated minute by minute (items 1-6) and overall for the whole coded period. A point was scored each time the communication partner confirmed the trial participant’s contribution. Additionally, it was noted whether the confirmation followed a digitised or a non-digitised contribution as this was not included in RAACS. The same was also done for the communication partner’s expansions. Descriptive statistics were used. The Wilcoxon signed ranked test and the Friedmann test were used to study differences between means between the study phases, between digitised and non-digitised communication and between the trial participants. An external coder coded 21 (22%) clips, selected through stratified random sampling, to assess inter-rater agreement (IRA). Both significance levels p < .05, and p < .005 were pre-set. A two-way mixed model, single-rater and absolute agreement IntraClass Correlation (ICC) was performed. A significance level

37 of p < .001 for IRA was pre-set. All analyses were performed using SPSS, version 25.0.

Results study IV The mean scores across items and trial participants ranged from 1.25 to 3.00. The RAACS score varied when the communication partner interacted with the different trial participants. One of the participants had a lower score for all items except for item 2, “adjusts physically”. Item for item, there was also a significant difference between the interactions across the study phases. The score was almost exclusively higher in Phase 2 when the communication partner used ALM. The difference was significant for RAACS-items 1-6. The communication partner more frequently confirmed and expanded on the trial participants’ digitised communication than on non-digitised communication. The differences were statistically significant (p < .05, and p < .005.)

Discussion study IV It should be noted that the findings of study IV are not possible to generalise, given that it was a case study. Nevertheless, the results highlight some areas for further research. Earlier research states that there is a difference in how communication partners to individuals with different diagnoses use responsive and scaffolding strategies (173). Findings from other studies (109, 119) suggest that it may be of interest to search for factors related to the non-speaking individual that may influence the communication partner’s use of these strategies. In study IV, the use of responsive and scaffolding strategies differed when interacting with different participants and under different conditions. The rate of confirmations and expansions were also higher when the trial participants communicated through the gaze-controlled device. This may have been what contributed to the higher RAACS score in the intervention phase, rather than whether the communication partner used ALM or not. Dig- itised communication may thus be useful to try when aiming to elicit responses from a communication partner.

38 General discussion

The overall aim of this thesis was to investigate communication intervention for individuals with Rett syndrome, especially aided symbol-based communication intervention and partner strategies. This general discussion will develop the overarching results regarding partner strategies, eye gaze communication, communication intervention for adults with Rett syndrome, and methodological considerations.

Intervention The studies in this thesis mainly involved what are described in the Interna- tional Classification of Functioning (ICF) as environmental factors, i.e. communication aids (products and technology), partner strategies (support and relationships), and the support (i.e. services, systems, and policies) provided by Speech Language Pathologists (SLPs). The outcome measures (including the tool that was developed in study II) were context dependent, implying that they had a focus on communicative participation rather than the individuals’ functioning in isolation.

Partner strategies In this thesis partner strategies have been examined from different angles. The content and format of the support provided by SLP services in Sweden were investigated in study I, responsive and scaffolding partner strategies were described in detail to deepen the understanding of these strategies in study II, and Aided Language Modelling (ALM) was applied as an independent variable in an intervention in study III. Aided interactions depend on the joint communication skills of non-speaking individuals and their communication partners. The studies therefore explored partner strategies that are used in naturalistic interactions rather than in task-based training. The strategies that were applied in study II-IV also targeted communicative functions related to interaction rather than requesting or choice making. Previous research of non- speaking individuals with and without Rett syndrome has to a large extent focused on the non-speaking individual and on teaching requesting and choice making (146, 147).

39 The definitions and measures of the term responsivity varies. In study IV the term responsive and scaffolding strategies (RSPS) were used and specified in detail according to the items in the Responsive Augmentative and Alterna- tive Communication Style scale (RAACS). The use of responsive strategies is context-dependent and consequently varied in interactions with different individuals, when the person communicated through a device or did not, or when Aided Language Modelling (ALM) was used or was not. This indicates that the application of RSPS varies when environmental factors are changed. There was unequal variation in the item scores and it may therefore be valuable to assess the use of RSPS in different situations and time points in an intervention. In study II, it was hypothesized that ALM would increase visual attention. The findings in the study were in line with this hypothesis and in study III ALM had an effect on one of the three participants’ visual attention in terms of focused gazes. Previous research indicates that attention may be improved by structured task-based training by a therapist (154). The findings in study II and III suggest that it may also be possible to influence visual attention by using ALM in naturalistic interaction. The clearest effect of ALM was to increase the participants’ variation of digitised expressions. When using ALM, the communication partner turned the pages in the vocabulary on the device, which may have drawn attention to new symbols that were relevant for the ongoing activity or topic and in addition, and the participants were provided access to a more varied vocabulary. The communication partner’s use of ALM in that way increased the participants’ variation of expressive vocabulary. Scaffolding strategies such as to recast and to expand on the individual’s communication behaviour are thought to facilitate language learning. Access to a larger variation of symbol-based communication may therefore result in a more linguistically stimulating environment (110, 141). It was not within the scope of this thesis to investigate language understanding before and after the intervention, which would have been desirable.

Eye gaze communication Given that eye gaze is the most commonly reported form of communication of individuals with Rett syndrome, this thesis investigated communication through gaze-controlled devices. As oculomotor function is apparently less affected than the hand function, gaze-controlled devices provide an alternative means to execute voluntary (goal-directed) actions and to access communication boards with graphic symbols. The participants in studies III and IV all frequently expressed digitised words which the communication partner confirmed and expanded on more frequently than was done on non-digitised communication. The participants also increased their expressive communication at the start of the intervention. However, their communicative intent was not

40 assessed and could therefore not be ascertained. Nevertheless, the participants had increased the number of voluntary actions that contributed to the interaction. These goal-directed actions are stated to be important to identify and respond to in order for these actions to become intentional (5, 174).

Communication intervention for adults with Rett syndrome The findings in study III underscore that it is possible for adults with Rett syndrome to increase their expressive communication. Adults increased their rate and variation of expressions during the intervention which is in line with previous intervention research where adults, as well as teenagers with Rett syndrome increased their communication skills (148, 150, 153, 160, 175). In study I, 42% of the participating SLPs worked at habilitation centres for adults. However, the distribution of SLP across the country varies and there are regions in Sweden without access to SLPs in the habilitation services for adults (174). Given that cognitive and communication skills are reported to be preserved in adulthood (47-50) and that systematic interventions seem to facilitate learning of communication skills, it is of great importance that individuals with Rett syndrome have access to communication intervention services throughout life.

Methodological discussion Rett syndrome is a rare disorder (18) and consequently observation studies are usually conducted with small samples. The findings are therefore not possible to generalise. However, measures were taken to conduct the studies in this thesis rigorously. These measures include assessment of inter-rater agreement (II-IV), non-respondent analysis (I), and adherence to established reporting guidelines (I, III). Several threats to the internal validity could be ruled out, thus strengthening the internal validity (63). Control for these threats was en- sured for order effect in study II, when assessing sensitivity to change, as well as for general health as a confounder in study III. In addition, treatment fidelity was assessed in study III. Below, methodological considerations regarding design, tools and measures will be discussed.

Design Four types of research designs were applied as they were judged to be able to answer the studies’ research questions. A cross-sectional survey was used to explore the service provided by SLPs to people with Rett syndrome in Swe- den. A qualitative approach (e.g. interviewing a smaller sample of SLPs) would have provided a more in-depth picture of the provided service. As practices have been found to vary across regions and it is likely that individuals

41 with Rett syndrome live in all Swedish regions, it was considered a priority to collect information that would be more able to be generalised. Study II was a descriptive psychometric study. Psychometric studies usually include data from a larger sample while study II was limited to 11 participants. The study included both development and evaluation of AVAI and all stages of the process were time-consuming, above all data collection, as the eligible participants lived far apart. No comparable tool existed, and a thorough development procedure was therefore necessary, at the expense of a larger study group. Study III was an experimental single case design (SCED), which is suited to evaluating intervention effects and one of the most common designs in AAC intervention research (146). SCED enables a high experimental control even when larger group studies are not possible, for example when involving individuals with rare conditions. One advantage with the design is also the possi- bility to evaluate the intervention session-by-session and modify the intervention when necessary (172). Finally, study IV was an exploratory case study as the aim was to explore and describe the use of a set of partner strategies that are often described and reported under the term responsivity.

Tools and measures The quality of research studies rests strongly on the quality of the instruments and measures that are used. They need to be psychometrically sound, i.e. the reliability, validity, and utility should be empirically tested. The same is applicable for tools used in clinical practice and there is a paucity of clinical tools and instruments that are evaluated psychometrically. Overall, few tools are used in clinical practice (88, 177), which was confirmed in study I. Tools and systematic procedures can also be used to evaluate and assess outcomes. Systematic tools further prevent arbitrary decisions and ensure that relevant information is collected and reliably measured. The tool Assessment of Visual Attention in Interaction (AVAI) was developed and evaluated in study II to assess visual attention and was applied in study III. The tool demonstrated acceptable inter-rater agreement, both in study II and study III with different external coders. Visual attention as assessed with AVAI, was deemed to be a context-dependent measure and sensitivity of change was therefore chosen as a validity measure. Sensitivity to change was demonstrated in both study II and study III. Construct validity could not be assessed as no other instrument was suitable for assessing visual attention in interaction. It was not within the scope of this work to assess clinical utility, (i.e. feasibility and usefulness). Utility in terms of acceptability to the participants was prioritised as this would indicate that the tool would be possible to use in research. Clinical utility remains to be assessed. Study III was exploratory in the sense that it did not use outcome measures that have been used in previous studies of ALM. It was considered necessary

42 to use measures that relied as little as possible on interpretation of communicative and linguistic intention and that were sensitive enough to be suitable as a continuous measure for individuals with Rett syndrome. The rate of digitised words and the rate of different digitised words that were used in study III were found to have good inter-rater agreement. An alternative would have been to use available instruments (13, 178, 179) although they require interpretation of intention or may not be sensitive to change.

Future directions Most urgent is to replicate study III to establish whether the findings are trans- ferable when environmental and personal factors vary, for example age or previous experience of gaze-controlled devices. Given the paucity of tools in clinical practice, it would be of value to investigate the clinical utility of AVAI. As the tool is time-consuming to administer, one alternative would be to develop a simpler procedure and evaluate psychometric properties. Further studies to examine the validity of AVAI are also needed. To assist instruction of communication partners, it would be of interest to investigate whether RAACS could be used in educating the communication partners and in that case, in what manner. Receptive vocabulary was not investigated in the intervention study. This is a logical next step for future research. The fact that methods for testing receptive language appear to be developing (57, 58) increase the feasibility of such studies. An important aim of communication intervention is to increase communication in the person’s natural environment. A next step would be to instruct the everyday communication partners to conduct the intervention that was used in study III. In such a study, it would be of interest to assess social validity in a systematic manner. It would also be desirable to involve the individual with Rett syndrome in the assessment of social validity. Finally, international guidelines for management of communication in Rett syndrome have recently been published (27). An important future research direction would be to conduct studies on the implementation of these guidelines and whether they would need to be adapted to Swedish conditions.

Conclusions and clinical implications The combined findings of the four studies in this thesis are in line with previous research suggesting that communication aids are beneficial for individuals with Rett syndrome. The results also highlight that gaze-controlled devices should be considered in communication intervention. Moreover, visual attention and the use of gaze-controlled devices vary among individuals with Rett syndrome. The communication partner’s use of facilitating strategies is context dependent, which was demonstrated by the detailed assessment with

43 RAACS. Neither literature, nor the studies in this thesis, provide clear guidance for which functions and personal or environmental factors influence the outcome of aided communication intervention the most. Therefore, comprehensive assessments as a base for decision regarding interventions, detailed monitoring during interventions and evaluations to take decisions about next steps, are necessary in clinical practice (27). Tools with satisfactory reliability, validity and utility (e.g. sensitive to change and clinical usefulness) are critical to such an evaluation. Given that the communication difficulties remain in adult age and that it is possible for adults to develop their communication, it is crucial that communication intervention services are available for individuals with Rett syndrome throughout their lifetime to ensure optimal communicative participation.

44 Acknowledgements

Words waves

Silence falls like a heavy veil I strain to say a word I get set Form my lips Take a deep breath It becomes a sort of noise Is it just a word? Is it just nonsense? Is it a word? Are words just words? Do they have any significance? Are they just waves? that are bobbing around never reaching anyone’s ear? Perhaps the waves can speak? Perhaps they carry a message Perhaps a question? Perhaps an explanation? Perhaps a feeling? The waves want to be inside someone’s ear Inside someone’s head To finally lift the veil And slowly, slowly creep deep inside someone’s heart

This poem was written by Carin Malmstedt Westerlund and translated by Jo- seph Bryan Davey. For me, it captures the essence of communication: to connect with other people. First of all, I would like to express my deepest gratitude to my supervisors throughout the whole project, Karin Sonnander and Per Lindberg. With indef- inite patience, knowledge and dedication, you have guided me through the process. I can not thank you enough for your invaluable support. I would also

45 like to thank Mariann Hedström who joined as supervisor for the final spurt. Your input and engagement have been highly valued. I am deeply grateful to everyone who has been part of the experiences leading up to my interest in AAC and research and to everyone who has contributed to this project. A spe- cial thanks to: • The individuals with Rett syndrome for participating, their families and care assistants for making this possible, Britt Claesson for performing the intervention, Helena Tegler, Kajsa Skytt, Karin Cloud Mildton and Märith Bergström Isacsson for coding and the SLPs for sharing your experiences. • Anna Lindam for statistical advice, Lisa Cockette and Adam Thomas for language checking of the thesis summary and papers I and II. • Åsa-Sara Sernheim and Rebecka Sernheim for the design of the cover. Åsa-Sara created the perfect symbol for this thesis. • Everyone in the research group Disability and Habilitation for stimulating discussions and making me feel welcome at the department: Karin Son- nander, Annika Terner, Gunnel Janeslätt, Ieva Reine, Johan Glad, Karin Jöreskog, Marie Lange, Mia Pless, Päivi Adolfsson, Ulrika Löfkvist, Öie Umb-Carlsson. • Former and current PhD students at the Department of Public Health and Caring Sciences. • The informal group of PhD students as well as companions on the quest for the perfect outcome measure: Anna Rensfeldt Flink, Helena Tegler and Linn Johnels. • Former and current colleagues at the National Center for Rett syndrome and related disorders for sharing their knowledge, ideas, advice and for much laughter: Adam Thomas, Elisabet Gabrielsson, Elisabeth Sun- deman, Eva Hamner, Gunilla Larsson, Gun-Marie Nyström, Ingegerd Witt Engerström, Lena Svedberg, Linn Johnels, Magnus Starbrink, Mari- anne Olsson, Martina Holmbom, Monika Dolik Michno, Märith Berg- ström Isacsson, Thomas Aronsson and Åsa-Sara Sernheim. • Anna Urbanowicz, Gill Townend, Sally-Ann Garrett and Theresa Bar- tolotta for a long and great time working together on the Rett syndrome communication guidelines. • Christina Bergsten, Inga-Lill Ek, Monica Bergh, Anna Ås, Carin Malm- stedt, Helene Lidström, Maria Borgestig, Petra Eklund and all other former colleagues at FBH for a fantastic time working together. • Rose-Marie Svensson for becoming my mentor and friend when I started as an SLP. I also want to express my gratitude to everyone at the habilitation centres in Bollnäs, Söderhamn and Mora.

I could not have done this without family and friends, of which some of you are already mentioned. Thank you for being such a great support on, and off, the rock all of you, and in particular Andreas, Anette, Anna & Jonas, Carin,

46 Cattis, Hilina, Magnus, Monika & Peo, Rakel, Rose-Marie, Svante and my relatives.

Finally, and most of all, I want to thank my parents, Rolf and Gunilla Wandin who have always believed me capable of anything and who themselves are capable of so much love, my sister Cecilia, the fighter with the most conta- gious laugh in the world, Gabriel and Hanna, my kind, fun and fantastic children.

47 References

1. Alant E, Uys K, Tönsing K. Communication, language, and literacy learning in children with developmental disabilities. In: Matson JL, Andrasik F, Matson ML. Treating childhood psychopathology and developmental disabilities. New York, NY: Springer 2009. p. 373-99 2. Olsson C. The kaleidoscope of communication: different perspectives on communication involving children with severe multiple disabilities. Stockholm: HLS Förlag; 2006. 3. Lloyd LL, Fuller DR, Arvidson HH. Augmentative and alternative communication: a handbook of principles and practices. Boston: Allyn and Bacon; 1997. 4. Bates E, Benigni L, Bretherton I, Camaioni L, Volterra V. The emergence of symbols. New York: Academic Press; 1979. 5. Goldbart J. Opening the communication curriculum to students with PMLDs. In: Ware J, editor. Educating children with profound and multiple learning difficulties. London: David Fulton Publish; 1994. 6. Hart B, Risley TR. Meaningful differences in the everyday experiences of young American children. Baltimore, MD: Paul. H. Brookes; 1995. 7. Topping K, Dekhinet R, Zeedyk S. Parent–infant interaction and children’s language development. Educ Psychol. 2013;33(4):391-426. https://doi.org/10.1080/01443410.2012.744159 8. Hoff E. How social contexts support and shape language development. Dev Rev. 2006;26(1):55-88. https://doi.org/10.1016/j.dr.2005.11.002 9. Pampoulou E. Graphic symbols terminology: a call for a consensus. J Enabling Technol. 2017;11(3):92-100. http://dx.doi.org/10.1108/JET-02-2017-0008 10. Beukelman D, Mirenda P. Augmentative and alternative communication: Sup- porting children and adults with complex communication needs. 4th ed. Balti- more, MD: Paul H. Brookes; 2013. 11. Dhondt A, Van keer I, van der Putten A, Maes B. Communicative abilities in young children with a significant cognitive and motor developmental delay. J Appl Res Intellect Disabil. 2020;33(3):529-41. https://doi.org/10.1111/jar.12695 12. Sigafoos J, Woodyatt G, Keen D, Tait K, Tucker M, Roberts-Pennell D, et al. Identifying potential communicative acts in children with developmental and physical disabilities. Commun Disord Q. 2000;21(2):77-86. http://dx.doi.org/10.1177/152574010002100202 13. Rowland C. Communication Matrix 2nd. ed. Oregon: University OHS, Design to Learn Projects; 2004. 14. Brady NC, Bruce S, Goldman A, Erickson K, Mineo B, Ogletree BT, et al. Com- munication services and supports for individuals with severe disabilities: guidance for assessment and intervention. Am J Intellect Dev Disabil. 2016;121(2):121-38. http://dx.doi.org/10.1352/1944-7558-121.2.121

48 15. Sigafoos J, Woodyatt G, Tucker M, Roberts-Pennell D, Pittendreigh N. Assess- ment of potential communicative acts in three individuals with Rett syndrome. J. Dev Phys Disabil. 2000;12(3):203-16. http://dx.doi.org/10.1023/A:1009461704556 16. Amir RE, Van den Veyver IB, Wan M, Tran CQ, Francke U, Zoghbi HY. Rett syndrome is caused by mutations in X-linked MECP2, encoding methyl-CpG- binding protein 2. Nat Genet. 1999;23(2):185-8. https://doi.org/10.1038/13810 17. Laurvick CL, de Klerk N, Bower C, Christodoulou J, Ravine D, Ellaway C, et al. Rett syndrome in Australia: a review of the epidemiology. J Pediatr. 2006;148(3):347-52. https://doi.org/10.1016/j.jpeds.2005.10.037 18. Fehr S, Bebbington A, Nassar N, Downs J, Ronen GM, de Klerk N, et al. Trends in the diagnosis of Rett syndrome in Australia. Pediatr Res. 2011;70: 311-19 https://doi.org/10.1203/PDR.0b013e3182242461 19. Neul JL, Kaufmann WE, Glaze DG, Christodoulou J, Clarke AJ, Bahi-Buisson N, et al. Rett syndrome: revised diagnostic criteria and nomenclature. Annals Neurol. 2010;68(6):944-50. https://doi.org/10.1002/ana.22124 20. Hagberg B, Witt‐Engerström I, Opitz JM, Reynolds JF. Rett syndr ome: a suggested staging system for describing impairment profile with increasing age towards adolescence. Am J Med Genet. 1986;25(S1):47-59. 21. Hagberg B. Clinical manifestations and stages of Rett syndrome. Ment Retard Dev Disabil Res Rev. 2002;8(2):61-5. 22. Sandweiss AJ, Brandt VL, Zoghbi HY. Advances in understanding of Rett syndrome and MECP2 duplication syndrome: prospects for future therapies. Lancet Neurol. 2020;19(8):689-98. https://doi.org/10.1016/S1474-4422(20)30217-9 23. Bisgaard A, Stahlhut M, Larsen J, Syhler B, Schönewolf-Greulich B. Is the regression period in Rett syndrome well defined and easy to recognize? Eur J Pae- diatr Neurol. 2015;19(1):S147. https://doi.org/10.1016/S1090-3798(15)30502-X 24. Einspieler C, Marschik PB. Regression in Rett syndrome: developmental path- ways to its onset. Neurosci Biobehav Rev. 2019;98:320-32. https://doi.org/10.1016/j.neubiorev.2019.01.028 25. Barnes KV, Coughlin FR, O'Leary HM, Bruck N, Bazin GA, Beinecke EB, Walco AC, Cantwell NG, Kaufmann WE. Anxiety-like behavior in Rett syndrome: characteristics and assessment by anxiety scales. J Neurodev Disord. 2015;7(1):30. DOI: 10.1186/s11689-015-9127-4. Epub 2015 Sep 15. PMID: 26379794; PMCID: PMC4571061. 26. Naidu S, Bibat G, Kratz L, Kelley RI, Pevsner J, Hoffman E, et al. Clinical vari- ability in Rett syndrome. J Child Neurol. 2003;18(10):662-8. https://doi.org/10.1177%2F08830738030180100801 27. Townend GS, Bartolotta TE, Urbanowicz A, Wandin H, Curfs LM. Development of consensus-based guidelines for managing communication of individuals with Rett syndrome. Augment Altern Commun. 2020;36(2):71-81. https://doi.org/10.1080/07434618.2020.1785009 28. Svedberg L, Herngren B, Michno P. How reconstructive surgery combined with physiotherapy for a painful nontraumatic patellar dislocation enabled a woman with Rett syndrome to become pain free and remain physically active: a case report. Clin Case Rep. 2019;7(3):542-5. https://dx.doi.org/10.1002%2Fccr3.2013 29. Downs J, Parkinson S, Ranelli S, Leonard H, Diener P, Lotan M. Perspectives on hand function in girls and women with Rett syndrome. Dev Neurorehabil. 2014;17(3):210-7. https://doi.org/10.3109/17518423.2012.758183 30. Urbanowicz A, Ciccone N, Girdler S, Leonard H, Downs J. Choice making in Rett syndrome: a descriptive study using video data. Disabil Rehabil. 2017;40(7):813-9. https://doi.org/10.1080/09638288.2016.1277392

49 31. Goldman S, Temudo T. Hand stereotypies distinguish Rett syndrome from autism disorder. Mov Disord. 2012;27(8):1060-2. https://doi.org/10.1002/mds.25057 32. Bartolotta, Zipp GP, Simpkins SD, Glazewski B. Communication skills in girls with Rett syndrome. Focus Autism Other Dev Disabil. 2011;26(1):15-24. DOI: 10.1177/1088357610380042 33. Fabio RA, Antonietti A, Castelli I, Marchetti A. Attention and communication in Rett Syndrome. Res Autism Spectr Disord. 2009;3(2):329-35. https://doi.org/10.1016/j.rasd.2008.07.005 34. de Breet LH, Townend GS, Curfs LM, Kingma H, Smeets EE, Lucieer F, et al. Challenges in evaluating the oculomotor function in individuals with Rett syndrome using electronystagmography. Eur J Paediatr Neurol. 2019;23(2):262-9. https://doi.org/10.1016/j.ejpn.2018.12.003 35. Rose SA, Wass S, Jankowski JJ, Feldman JF, Djukic A. Impaired visual search in children with Rett syndrome. Pediatr Neurol. 2019;92:26-31. doi.org/10.1016/j.pediatrneurol.2018.10.002 36. Rose SA, Wass S, Jankowski JJ, Feldman JF, Djukic A. Attentional shifting and disengagement in Rett syndrome. Neuropsychol. 2019;33(3):335-42. http://dx.doi.org/10.1037/neu0000515 37. Townend GS, van de Berg R, de Breet LH, Hiemstra M, Wagter L, Smeets E, et al. Oculomotor function in individuals with Rett syndrome. Pediatr Neurol. 2018;88:48-58. https://doi.org/10.1016/j.pediatrneurol.2018.08.022 38. Didden R, Sigafoos J, Korzilius H, Baas A, Lancioni GE, O’Reilly MF, et al. Form and function of communicative behaviours in idividuals with Angelman syndrome. J Appl Res Intellect Disabil. 2009;22(6):526-37. https://doi.org/10.1111/j.1468-3148.2009.00520.x 39. Lavås J, Slotte A, Jochym-Nygren M, van Doorn J, Witt Engerström I. Commu- nication and eating proficiency in 125 females with Rett syndrome: the Swedish Rett center survey. Disabil Rehabil. 2006;28(20):1267-79. https://doi.org/10.1080/09638280600554868 40. Urbanowicz A, Downs J, Girdler S, Ciccone N, Leonard H. Aspects of speech- language abilities are influenced by MECP2 mutation type in girls with Rett syndrome. Am J Med Genet. 2015;167(2):354-62. doi.org/10.1002/ajmg.a.36871 41. Sandberg AD, Ehlers S, Hagberg B, Gillberg C. The Rett syndrome complex: communicative functions in relation to developmental level and autistic features. autism. 2000;4(3):249-67. https://doi.org/10.1177%2F1362361300004003003 42. Urbanowicz A, Leonard H, Girdler S, Ciccone N, Downs J. Parental perspectives on the communication abilities of their daughters with Rett syndrome. Dev Neu- rorehabil. 2016;19(1):17-25. https://doi.org/10.3109/17518423.2013.879940 43. Von Tetzchner S. Communication skills among females with Rett syndrome. Eur Child Adolesc Psychiatry. 1997;6(S1):33-37. 44. Djukic A, Valicenti McDermott M. Social preferences in Rett syndrome. Pediatr Neurol. 2012;46(4):240-2. https://doi.org/10.1016/j.pediatrneurol.2012.01.011 45. Olsson B. Autistic traits in the Rett syndrome. Brain Dev. 1987;9(5):491-8. 46. Sernheim Å-S, Hemmingsson H, Witt Engerström I, Liedberg G. Activities that girls and women with Rett syndrome liked or did not like to do. Scandi J Occup Ther. 2016;25(4):267-77. https://doi.org/10.1080/11038128.2016.1250812 47. Halbach N, Smeets E, Steinbusch C, Maaskant M, van Waardenburg D, Curfs L. Aging in Rett syndrome: a longitudinal study. Clin Genet. 2013;84(3):223-9. https://doi.org/10.1111/cge.12063 48. Cianfaglione R, Clarke A, Kerr M, Hastings RP, Oliver C, Felce D. Ageing in Rett syndrome. J Intellect Disabil Res. 2016;60(2):182-90. https://doi.org/10.1111/jir.12228

50 49. Schönewolf-Greulich B, Stahlhut M, Larsen JL, Syhler B, Bisgaard A-M. Func- tional abilities in aging women with Rett syndrome–the Danish cohort. Disabil Rehabil. 2017;39(9):911-8. https://doi.org/10.3109/09638288.2016.1170896 50. Vignoli A, La Briola F, Peron A, Turner K, Savini M, Cogliati F, et al. Medical care of adolescents and women with Rett syndrome: an Italian study. Am J Med Genet A. 2012;158A:13-18. https://doi.org/10.1002/ajmg.a.34367 51. Neul JL, Lane JB, Lee H-S, Geerts S, Barrish JO, Annese F, et al. Developmental delay in Rett syndrome: data from the natural history study. J Neurodev Disord. 2014;6(20):1-9. https://doi.org/10.1186/1866-1955-6-20 52. Marschik PB, Pini G, Bartl-Pokorny KD, Duckworth M, Gugatschka M, Voll- mann R, et al. Early speech-language development in females with Rett syndrome: focusing on the preserved speech variant. Dev Med Child Neurol. 2012;54(5):451-6. https://doi.org/10.1111/j.1469-8749.2012.04123.x 53. Bartl-Pokorny KD, Marschik PB, Sigafoos J, Tager-Flusberg H, Kaufmann WE, Grossmann T, et al. Early socio-communicative forms and functions in typical Rett syndrome. Res Dev Disabil. 2013;34(10):3133-8. https://doi.org/10.1016/j.ridd.2013.06.040 54. Bisgaard A-M, Schönewolf-Greulich B, Ravn K, Rønde G. Is it possible to diag- nose Rett syndrome before classical symptoms become obvious? Review of 24 Danish cases born between 2003 and 2012. Eur J Paediatr Neurol. 2015;19(6):679-87. https://doi.org/10.1016/j.ejpn.2015.07.004 55. Woodyatt G, Ozanne A. Communication abilities and Rett syndrome. J Autism Dev Disord. 1992;22(2):155-73. https://doi.org/10.1007/BF01058148 56. Woodyatt G, Ozanne A. Intentionality and communication in four children with Rett syndrome. Aust N Z J Dev Disabil1994;19(3):173-84. 57. Ahonniska-Assa J, Polack O, Saraf E, Wine J, Silberg T, Nissenkorn A, et al. Assessing cognitive functioning in females with Rett syndrome by eye-tracking methodology. Eur J Paediatr Neurol. 2017;22(1):29-35. https://doi.org/10.1016/j.ejpn.2017.09.010 58. Clarkson T, LeBlanc J, DeGregorio G, Vogel-Farley V, Barnes K, Kaufmann WE, et al. Adapting the Mullen Scales of Early Learning for a Standardized Measure of Development in Children With Rett Syndrome. Intellect Dev Disabil. 2017;55(6):419-31. DOI: 10.1352/1934-9556-55.6.419 59. Didden R, Korzilius H, Smeets E, Green VA, Lang R, Lancioni GE, et al. Com- munication in individuals with Rett syndrome: an assessment of forms and functions. J Dev Phys Disabil. 2010;22(2):105-18. oi:10.1007/s10882-009-9168-2 60. Urbanowicz A, Downs J, Girdler S, Ciccone N, Leonard H. An exploration of the use of eye gaze and gestures in females with Rett syndrome. J Speech Lang Hear. 2016;59(6):1373-83. DOI: 10.1044/2015_JSLHR-L-14-0185 61. Demeter K. Assessing the developmental level in Rett syndrome: an alternative approach? Eur Child Adolesc Psychiatry. 2000;9(3):227-33. https://doi.org/10.1007/s007870070047 62. Sigafoos J, Kagohara D, van der Meer L, Green VA, O’Reilly MF, Lancioni GE, et al. Communication assessment for individuals with Rett syndrome: A systematic review. Res Autism Spectr Disord. 2011;5(2):692-700. 10.1007/s007870070047 63. Kazdin AE. Research design in clinical psychology. 4th ed. Boston: Pearson Ed- ucation; 2013. 64. Yoder P, Symons FJ. Observational measurement of behavior. New York: Springer Publishing, Co Inc.; 2010. 65. Hintze JM. Psychometrics of direct observation. School Psychol Rev. 2005;34(4):507-19.

51 66. Streiner DL, Norman GR. Health measurement scales - a practical guide to their development and use. 4th ed. New York: Oxford University Press; 2008. 67. Ferguson JL, Cihon JH, Leaf JB, Van Meter SM, McEachin J, Leaf R. Assess- ment of social validity trends in the journal of applied behavior analysis. Eur J Behav Anal. 2019;20(1):146-57. https://doi.org/10.1080/15021149.2018.1534771 68. Glad J, Jergeby U, Gustafsson C, Sonnander K. Social work practitioners' experience of the clinical utility of the home observation for measurement of the environment (HOME) inventory. Child Fam Soc Work. 2012;17(1):23-33. https://doi.org/10.1111/j.1365-2206.2011.00769.x 69. Mullen EM. Infant MSEL manual: infant Mullen scales of early learning: Circle Pines, MN: American Guidance Service; 1989. 70. Sparrow SS, Cicchetti DV, Balla DA. Vineland adaptive behavior scales Vine- land-II: survey forms manual: Pearson Minneapolis, MN; 2005. 71. Mundy P, Delgado C, Block J, Venezia M, Hogan A, Seibert J. early social communication scales (ESCS). Miami: University of Miami; 2003. 72. Seibert JM, Hogan AE, Mundy PC. Assessing interactional competencies: The early social‐communication scales. Infant Ment Health J. 1982;3 (4):244-58. https://doi.org/10.1002/1097-0355(198224)3:4%3C244::AID- IMHJ2280030406%3E3.0.CO;2-R 73. Rowland C, Fried-Oken M. Communication Matrix: a clinical and research assessment tool targeting children with severe communication disorders. J Pediatr Rehabil Med. 2010;3(4):319-329. DOI: 10.3233/PRM-2010-0144 74. Grether SM. AAC Supports for individuals with Rett syndrome across the lifespan. Perspect Augment Altern Commun. 2015;24(3):74-85. https://doi.org/10.1044/aac24.3.74 75. Rowland C. Using the communication matrix to assess expressive skills in early communicators. Commun Disord Q. 2011;32(3):190-201. https://doi.org/10.1177%2F1525740110394651 76. Kiresuk T, Smith A, Cardillo J. Goal attainment scaling: applications, theory, and measurement. Hillsdale (NJ): Lawrence Erlbaum; 1994. 77. Schlosser RW. Goal attainment scaling as a clinical measurement technique in communication disorders: a critical review. J Commun Disord. 2004;37(3):217- 39. https://doi.org/10.1016/j.jcomdis.2003.09.003 78. World Health Organization. International classification of functioning, disability and health (ICF). Geneva: World Health Organization; 2001. 79. Nowak HI, Broberg M, Starke M. Parents’ experience of support in Sweden: Its availability, accessibility, and quality. J Intellect Disabil. 2013;17(2):134-44. 80. Brennan C, Traustadóttir R, Rice J, Anderberg P. Negotiating independence, choice and autonomy: experiences of parents who coordinate personal assistance on behalf of their adult son or daughter. Disabil Soc. 2016;31(5):604-21. https://doi.org/10.1080/09687599.2016.1188768 81. Lilja M, Månsson I, Jahlenius L, Sacco-Peterson M. Disability policy in Sweden: Policies concerning assistive technology and home modification services. J Disabil Policy Stud. 2003;Winter(14):130-35.DOI: 10.1177/10442073030140030101 82. Lindstedt H, Umb-Carlsson Ö. Cognitive assistive technology and professional support in everyday life for adults with ADHD. Disabil Rehabil Assist Technol. 2013;8(5)402-8. https://doi.org/10.3109/17483107.2013.769120 83. Hustad KC, Miles MS. Alignment between augmentative and alternative communication needs and school-based speech-language services provided to young children with cerebral palsy. Early Child Serv. 2010;4(3):129-40.

52 84. Siu E, Tam E, Sin D, Ng C, Lam E, Chui M, et al. A survey of augmentative and alternative communication service provision in Hong Kong. Augment Altern Commun. 2010;26(4):289-98. DOI: 10.3109/07434618.2010.521894 85. Wormnæs S, Abdel Malek Y. Egyptian speech therapists want more knowledge about augmentative and alternative communication. Augment Altern Commun. 2004;20(1):30-41. DOI: 10.1080/07434610310001629571 86. Starble A, Hutchins T, Favro MA, Prelock P, Bitner B. Family-centered intervention and satisfaction with AAC device training. Commun Disord Q. 2005;27(1):47-54. DOI: 10.1177/15257401050270010501 87. Holmqvist E, Thunberg G, Peny Dahlstrand M. Gaze-controlled communication technology for children with severe multiple disabilities: parents and professionals’ perception of gains, obstacles, and prerequisites. Assist Technol. 2018;30(4):201-208. https://doi.org/10.1080/10400435.2017.1307882 88. Tegler H, Pless M, Blom Johansson M, Sonnander K. Speech and language pathologists’ perceptions and practises of communication partner training to support children’s communication with high-tech speech generating devices. Disabil Rehabil Assist Technol. 2018;14(6):581-9. https://doi.org/10.1080/17483107.2018.1475515 89. Moorcroft A, Scarinci N, Meyer C. A systematic review of the barriers and facilitators to the provision and use of low-tech and unaided AAC systems for people with complex communication needs and their families. Disabil Rehabil Assist Technol. 2019;14(7):710-31. https://doi.org/10.1080/17483107.2018.1499135 90. Branson D, Demchak M. The use of augmentative and alternative communication methods with infants and toddlers with disabilities: a research review. Augment Altern Commun. 2009;25(4):274-86. DOI: 10.3109/07434610903384529 91. Drager KDR, Light J, McNaughton D. Effects of AAC interventions on communication and language for young children with complex communication needs. J Pediatr Rehabil Med. 2010;3(4):303-10. DOI: 10.3233/PRM-2010-0141 92. Light J, Mcnaughton D. Designing AAC research and intervention to improve outcomes for individuals with complex communication needs. Augment Altern Commun. 2015;31(2):85-96. DOI: 10.3109/07434618.2015.1036458 93. McNaughton D, Bryen D, Blackstone S, Williams M, Kennedy P. Young Adults with Complex Communication Needs: Research and Development in AAC for a “Diverse” Population. Assist Technol. 2012;24(1):45-53. https://doi.org/10.1080/10400435.2011.648715 94. Karlsson P, Allsop A, Dee-Price B-J, Wallen M. Eye-gaze control technology for children, adolescents and adults with cerebral palsy with significant physical disability: Findings from a systematic review. Dev Neurorehabil. 2018;21(8):497- 505. https://doi.org/10.1080/17518423.2017.1362057 95. Bayldon HJ. A dialogic reading intervention incorporating AAC modelling and increased communication partner responsiveness during shared storybook reading with children with complex physical, cognitive, and sensory needs who use partner assisted scanning, Albany, New Zealand: Massey University; 2018. 96. Townend G, Bartolotta TE, Urbanowicz A, Wandin H, Curfs LMG. Rett syndrome communication guidelines: a handbook for therapists, educators and families. Cincinnati, OH: Rettsyndrome.org; 2020. 97. Yu C. Embodied active vision in language learning and grounding. In: Paletta L, Rome E, editors. Attention in cognitive systems Theories and systems from an interdisciplinary viewpoint WAPCV 2007 Lecture notes in computer science. 4840. Berlin, Heidelberg: Springer; 2007:75-90. https://doi.org/10.1007/978-3- 540-77343-6_5

53 98. Yu C, Smith L. Joint attention without gaze following: human infants and their parents coordinate visual attention to objects through eye-hand coordination. PLoS ONE. 2013; 8(11). Available from https://doi.org/10.1371/journal.pone.0079659 99. Benigno JP, McCarthy JW. Aided Symbol-Infused Joint Engagement. Child Dev Perspect. 2012;6(2):181-6. https://doi.org/10.1111/j.1750-8606.2012.00237.x 100. Light J, Wilkinson KM, Thiessen A, Beukelman DR, Fager SK. Designing effec- tive AAC displays for individuals with developmental or acquired disabilities: state of the science and future research directions. Augment Altern Commun. 2019;35(1):42-55. DOI: 10.1080/07434618.2018.1558283 101. Kent-Walsh J, Murza KA, Malani MD, Binger C. Effects of communication partner instruction on the communication of individuals using AAC: a meta-analysis. Aug- ment Altern Commun. 2015;31(4):271-84. doi. 10.3109/07434618.2015.1052153 102. Murray J, Goldbart J. Augmentative and alternative communication: a review of current issues. Paediatr Child Health. 2009;19(10):464-8. https://doi.org/10.1016/j.paed.2009.05.003 103. McNaughton D, Light J, Beukelman DR, Klein C, Nieder D, Nazareth G. Build- ing capacity in AAC: A person-centred approach to supporting participation by people with complex communication needs. Augment Altern Commun. 2019;35(1):56-68. DOI: 10.1080/07434618.2018.1556731 104. Kent-Walsh J, McNaughton D. Communication partner instruction in AAC: present practices and future directions. Augment Altern Commun. 2005;21(3):195- 204. doi=10.1080/07434610400006646 105. Kent-Walsh J, Binger C, Malani M. Teaching partners to support the communication skills of young children who use AAC: Lessons from the ImPAACT program. Early Child Serv. 2010;4(3):155-70. 106. Rensfeldt Flink A, Åsberg Johnels J, Broberg M, Thunberg G. Examining perceptions of a communication course for parents of children with profound intellectual and multiple disabilities. Int J Dev Disabil. 2020:1-12. doi.org/10.1080/20473869.2020.1721160 107. Cabell SQ, Justice LM, Piasta SB, Curenton SM, Wiggins A, Turnbull KP, et al. The impact of teacher responsivity education on preschoolers' language and literacy skills. Am J Speech Lang Pathol. 2011;20(4):315-30. DOI: 10.1044/1058- 0360(2011/10-0104) 108. Fey ME, Warren SF, Brady N, Finestack LH, Bredin-Oja SL, Fairchild M, et al. Early Effects of Responsivity Education/Prelinguistic Milieu Teaching for Chil- dren With Developmental Delays and Their Parents. J Speech Lang Hear Res. 2006;49(3):526-47. 109. Warren SF, Brady NC. The role of maternal responsivity in the development of children with intellectual disabilities. Ment Retard Dev Disabil Res Rev. 2007;13(4):330-8. https://doi.org/10.1002/mrdd.20177 110. Broberg M, Ferm U, Thunberg G. Measuring responsive style in parents who use AAC with their children: development and evaluation of a new instrument. Aug- ment Altern Commun. 2012;28(4):243-253. DOI: 10.3109/07434618.2012.740686 111. Mahoney G, Powell A, Finger I. The maternal behavior rating scale. Topics Early Child Spec Ed. 1986;6(2):44-56. doi.org/10.1177%2F027112148600600205 112. Mahoney G. The Maternal Behavior Rating Scale-Revised. Mandel School of Applied Social Sciences. 2008. 113. Pennington L, Thomson K, James P, Martin L, McNally R. Effects of it takes two to talk—the Hanen program for parents of preschool children with cerebral palsy: findings from an exploratory study. J Speech Lang Hear Res. 2009;52(5):1121- 38.

54 114. Karaaslan O, Mahoney G. Mediational analyses of the effects of responsive teaching on the developmental functioning of preschool children with disabilities. J Early Interv. 2015;37(4):286-299. DOI: 10.1177/1053815115617294 115. Mahoney G, Perales F. Relationship-focused early intervention with children with pervasive developmental disorders and other disabilities: a comparative study. J Dev Behav Pediatr. 2005;26(2):77-85. DOI: 0196-206X/05/2602-0077 116. Brown JA, Woods JJ. Parent-implemented communication intervention: Sequen- tial analysis of triadic relationships. Topics Early Child Spec Ed. 2016;36(2):115- 24. https://doi.org/10.1177%2F0271121416628200 117. Haebig E, McDuffie A, Ellis Weismer S. Brief Report: Parent Verbal Respon- siveness and Language Development in Toddlers on the Autism Spectrum. J Au- tism Dev Disord. 2013;43(9):2218-27. DOI: 10.1007/s10803-013-1763-5 118. Siller M, Hutman T, Sigman M. A parent-mediated intervention to increase responsive parental behaviors and child communication in children with ASD: a randomized clinical trial. J Autism Dev Disord. 2013;43(3):540-55. DOI: 10.1007/s10803-012-1584-y 119. Karaaslan O, Mahoney G. Effectiveness of responsive teaching with children with Down syndrome. Ment Retard. 2013;51(6):458-69. DOI: 10.1352/1934- 9556-51.6.458 120. Harwood K, Warren S, Yoder P. The importance of responsivity in developing contingent exchanges with beginning communicators. In: Reichle J, editor. Ex- emplary practices for beginning communicators: Implications for AAC. Balti- more, Md: Paul H. Brookes Publishing; 2002. p. 59-95. 121. Yoder PJ, Warren SF. Maternal responsivity mediates the relationship between prelinguistic intentional communication and later language. J Early Interv. 1999;22(2):126-36. https://doi.org/10.1177%2F105381519902200205 122. Van Keer I, Colla S, Van Leeuwen K, Vlaskamp C, Ceulemans E, Hoppen- brouwers K, et al. Exploring parental behavior and child interactive engagement: A study on children with a significant cognitive and motor developmental delay. Res Dev Disabil. 2017;64:131-42. https://doi.org/10.1016/j.ridd.2017.04.002 123. Van Keer I, Bodner N, Ceulemans E, Van Leeuwen K, Maes B. Parental behavior and child interactive engagement: a longitudinal study on children with a significant cognitive and motor developmental delay. Res Dev Disabil. 2020;103:1-11 https://doi.org/10.1016/j.ridd.2020.103672 124. Cress CJ, Grabast J, Burgers Jerke K. Contingent interactions between parents and young children with severe expressive communication impairments. Com- mun Disord Q. 2013;34(2):81-96. doi.org/10.1177%2F1525740111416644 125. Medeiros KF, Cress CJ. Differences in maternal responsive and directive behavior during free play with and without aided AAC. Augment Altern Commun. 2016;32(2):151-61. DOI: 10.1080/07434618.2016.1179341 126. Andersson L, Eriksson T. Responsivitet hos föräldrar till barn med flerfunktions- nedsättningar: Spelar lektyp roll? [Responsivity of parents of children with profound intellectual and multiple disabilities: Does play type matter?]. Gothenburg: University of Gothenburg; 2019. 127. Piasta SB, Justice LM, Cabell SQ, Wiggins AK, Turnbull KP, Curenton SM. Im- pact of professional development on preschool teachers’ conversational responsivity and children's linguistic productivity and complexity. Early Child Res Q. 2012;27(3):387-400. https://doi.org/10.1016/j.ecresq.2012.01.001 128. Penne A, ten Brug A, Munde V, van der Putten A, Vlaskamp C, Maes B. Staff interactive style during multisensory storytelling with persons with profound intellectual and multiple disabilities. J Intellect Disabil Res. 2012;56(2):167-78. DOI: 10.1111/j.1365-2788.2011.01448.x

55 129. Hostyn I, Petry K, Lambrechts G, Maes B. Evaluating the quality of the interaction between persons with profound intellectual and multiple disabilities and direct support staff: a preliminary application of three observation scales from parent–infant research. J Appl Res Intellect Disabil. 2011;24(5):407-20. https://doi.org/10.1111/j.1468-3148.2010.00618.x 130. Stockwell K, Alabdulqader E, Jackson D, Basu A, Olivier P, Pennington L. Fea- sibility of parent communication training with remote coaching using smartphone apps. Int J Lang Commun Disord. 2019;54(2):265-280. https://doi.org/10.1111/1460-6984.12468 131. Sennott S, Light JC, McNaughton D. AAC modeling intervention research review. Res Pract Persons Severe Disabil. 2016;41(2):101-15. DOI: 10.1177/1540796916638822 132. Allen AA, Schlosser RW, Brock KL, Shane HC. The effectiveness of aided augmented input techniques for persons with developmental disabilities: a systematic review. Augment Altern Commun. 2017;33(3):149-59. DOI: 10.1080/07434618.2017.1338752 133. Kent-Walsh J, Binger C, Hasham Z. Effects of parent instruction on the symbolic communication of children using augmentative and alternative communication during storybook reading. Am J Speech Lang Pathol. 2010;19(2):97-107.DOI: 10.1044/1058-0360(2010/09-0014) 134. Rosa-Lugo LI, Kent-Walsh J. Effects of parent instruction on communicative turns of Latino children using augmentative and alternative communication during storybook reading. Commun Disord Q. 2008;30(1):49-61. DOI: 10.1177/1525740108320353 135. Koppenhaver DA, Erickson KA, Harris B, McLellan J, Skotko BG, Newton RA. Storybook-based communication intervention for girls with Rett syndrome and their mothers. Disabil Rehabil. 2001;23(3-4):149-59. DOI: 10.1080/09638280150504225. 136. Dada S, Alant E. The effect of aided language stimulation on vocabulary acqui- sition in children with little or no functional speech. Am J Speech Lang Pathol. 2009;18(1):50-64. 137. Drager KDR, Postal VJ, Carrolus L, Castanello M, Gagliano C, Glynn J. The effect of aided language modeling on symbol comprehension and production in two preschoolers with autism. Am J Speech Lang Pathol. 2006;15:112-25. 138. Harris MD, Reicle J. The impact of aided language stimulation on symbol comprehension and production in children with moderate cognitive disabilities. Am J Speech Lang Pathol. 2004;13:155-67. 139. Binger C, Kent-Walsh J, Berens J, Del Campo S, Rivera D. Teaching latino parents to support the multi-symbol message productions of their children who require AAC. Augment Altern Commun. 2008;24(4):323-38. DOI: 10.1080/07434610802130978 140. Binger C, Kent-Walsh J, Ewing C, Taylor S. Teaching educational assistants to facilitate the multisymbol message productions of young students who require augmentative and alternative communication. Am J Speech Lang Pathol. 2010;19(2):108-20. DOI: 10.1044/1058-0360(2009/09-0015) 141. Binger C, Maguire-Marshall M, Kent-Walsh J. Using aided AAC models, recasts, and contrastive targets to teach grammatical morphemes to children who use AAC. J Speech Lang Hear Res. 2011;54(1):160-76A.DOI: 10.1044/1092- 4388(2010/09-0163) 142. Solomon-Rice PL, Soto G. Facilitating vocabulary in toddlers using AAC: a preliminary study comparing focused stimulation and augmented input. Commun Disord Q. 2014;35(4):204-15.DOI: 10.1177/1525740114522856

56 143. Dorney KE, Erickson K. Transactions within a classroom-based AAC intervention with preschool students with autism spectrum disorders: a mixed-methods investigation. Except Educ Int. 2019;29(2):42-58. 144. Flores JL. Examining aided input intervention in a classroom setting for children labeled with significant disabilities. University of northern Iowa; 2016. 145. Light J, McNaughton D. The changing face of augmentative and alternative communication: past, present, and future challenges. Augment Altern Commun. 2012;28(4):197-204. 146. McNaughton D, Light J. What we write about when we write about AAC: The past 30 years of research and future directions. Augment Altern Commun. 2015;31(4):261-70.DOI: 10.3109/07434618.2012.737024 147. Lim J, Greenspoon D, Hunt A, McAdam L. Rehabilitation interventions in Rett syndrome: a scoping review. Dev Med Child Neurol. 2020;62(8):906-16. DOI: 10.1111/dmcn.14565 148. Ainsworth MK, Evmenova AS, Behrmann M, Jerome M. Teaching phonics to groups of middle school students with autism, intellectual disabilities and complex communication needs. Res Dev Disabil. 2016;56:165-76. https://doi- org.ezproxy.its.uu.se/10.1016/j.ridd.2016.06.001 149. Baptista P, Mercadante M, Macedo E, Schwartzman J. Cognitive performance in Rett syndrome girls: a pilot study using eyetracking technology. J Intellect Disa- bil Res. 2006;50(9):662-6. DOI: 10.1111/j.1365-2788.2006.00818.x 150. Byiers BJ, Dimian A, Symons FJ. Functional communication training in Rett syndrome: a preliminary study. Am J Intellect Dev Disabil. 2014;119(4):340-50. 151. Elefant C, Wigram T. Learning ability in children with Rett syndrome. Brain Dev. 2005;27(Suppl 1):S97-S101.DOI: 10.1352/1944-7558-119.4.340 152. Simacek J, Reichle J, McComas J. Communication intervention to teach requesting through aided AAC for two learners with Rett syndrome. J Dev Phys Disabil. 2016;28(1):59-81.DOI: 10.1007/s10803-016-3006-z 153. Fabio RA, Castelli I, Marchetti A, Antonietti A. Training communication abilities in Rett Syndrome through reading and writing. Front Psychol. 2013;4. DOI: 10.3389/fpsyg.2013.00911 154. Fabio RA, Giannatiempo S, Oliva P, Murdaca AM. The increase of attention in Rett syndrome: a pre-test/post-test research design. J Dev Phys Disabil. 2011;23(2):99-111. DOI: 10.1007/s10882-010-9207-z 155. Hetzroni O, Rubin C, Konkol O. The use of assistive technology for symbol iden- tification by children with Rett syndrome. J Intellect Dev Disabil. 2002;27(1):57- 71. DOI: 10.1080/13668250120119626-1 156. Lancioni G, Singh N, O’Reilly M, Sigafoos J, Boccasini A, La Martire M, et al. Microswitch-aided programs for a woman with Rett syndrome and a boy with extensive neuro-motor and intellectual disabilities. J Dev Phys Disabil. 2014;26(2):135-43.DOI: 10.1007/s10882-013-9349-x 157. Stasolla F, De Pace C, Damiani R, Di Leone A, Albano V, Perilli V. Comparing PECS and VOCA to promote communication opportunities and to reduce stereo- typed behaviors by three girls with Rett syndrome. Res Autism Spectr Disord. 2014;8(10):1269-78. https://doi- org.ezproxy.its.uu.se/10.1016/j.rasd.2014.06.009 158. Stasolla F, Perilli V, Di Leone A, Damiani R, Albano V, Stella A, et al. Technological aids to support choice strategies by three girls with Rett syndrome. Res Dev Disabil. 2015;36:36-44. https://doi-org.ezproxy.its.uu.se/10.1016/j.ridd.2014.09.017 159. Simacek J, Dimian AF, McComas JJ. Communication intervention for young children with severe neurodevelopmental disabilities via telehealth. J Autism Dev Disord. 2017;47(3):744-67. DOI: 10.1007/s10803-016-3006-z

57 160. Vessoyan K, Steckle G, Easton B, Nichols M, Mok Siu V, McDougall J. Using eye-tracking technology for communication in Rett syndrome: perceptions of impact. Augment Altern Commun. 2018;34(3):230-41. DOI: 10.1080/07434618.2018.1462848 161. SurveyMonkey.com. [web page]. Palo Alto, California, USA: Survey- Monkey.com, LLC; 2013 [Available from: http://surveymonkey.com/. 162. Hourcade J, Everhart Pilotte T, West E, Parette P. A history of augmentative and alternative communication for individuals with severe and profound disabilities. Focus Autism Other Dev Disabl. 2004;19(4):235-44. 163. Calculator S, Black T. Validation of an Inventory of Best Practices in the Provi- sion of Augmentative and Alternative Communication Services to Students With Severe Disabilities in General Education Classrooms. Am J Speech Lang Pathol. 2009;18:329-42. 164. Binger C, Ball L, Dietz A, Kent-Walsh J, Lasker J, Lund S, et al. Personnel roles in the AAC assessment process. Augment Altern Commun. 2012;28(4):278-88. DOI: 10.3109/07434618.2012.716079 165. Koegel RL, Frea WD. Treatment of social behavior in autism through the modification of pivotal social skills. J Appl Behav Anal. 1993;26(3):369-77. DOI: 10.1901/jaba.1993.26-369 166. Adamson LB, Bakeman R, Deckner DF, Romski M. Joint engagement and the emergence of language in children with autism and Down syndrome. J Autism Devel Disord. 2009;39(1):84-96. DOI: 10.1007/s10803-008-0601-7 167. Yoder P, Compton D. Identifying predictors of treatment response. Ment Retard Devel Disabil Res Rev. 2004;10(3):162-8. https://doi- org.ezproxy.its.uu.se/10.1002/mrdd.20013 168. Calculator SN. Parents' perceptions of communication patterns and effectiveness of use of augmentative and alternative communication systems by their children with Angelman syndrome. Am J Speech Lang Pathol. 2014;23(4):562-73. DOI: 10.1044/2014_AJSLP-13-0140 169. Sutherland DE, Gillon GG, Yoder DE. AAC use and service provision: a survey of New Zealand speech-language therapists. Augment Altern Commun. 2005;21(4):295-307. DOI: 10.1080/07434610500103483 170. King J. Preliminary survey of speech-language pathologists providing AAC services in health care settings in Nebraska. Augment Altern Commun. 1998;14(4):222-7. DOI: 10.1080/07434619812331278396 171. Munde, V., Vlaskamp, C., Ruijssenaars, W., & Nakken, H. Determining alertness in individuals with profound intellectual and multiple disabilities: the reliability of an observation list. Educ Training Autism Dev Disabil. 2011:116-23. https://www.jstor.org/stable/23880035 172. Lane JD, Ledford JR, Gast DL. Single-case experimental design: Current stand- ards and applications in occupational therapy. Am J Occup Ther. 2017;71(2): DOI: 10.5014/ajot.2017.022210 173. Brooks-Gunn J, Lewis M. Maternal responsivity in interactions with handicapped infants. Child Dev. 1984;55:782-93. DOI: 10.2307/1130129 174. Mats Granlund & Cecilia Olsson. Efficacy of communication intervention for presymbolic communicators, Augmentative and Alternative Communication. 1999;15:1, 25-37, DOI: 10.1080/07434619912331278545 175. Sigafoos J, Laurie S, Pennell D. Teaching children with Rett syndrome to request preferred objects using aided communication: Two preliminary studies. Augment Altern Commun. 1996;12(2):88-96. DOI: 10.1080/07434619612331277538

58 176. Wandin H, Sonnander K, Lindberg P. Habiliteringslogopeden i fokus: Beskriv- ning av kårens sammansättning och arbetsmässiga förutsättningar–resultat av en enkätstudie. Logopeden. 2015(3):18-21. Available from: https://issuu.com/logopeden/docs/logopeden_3_2015_issu_st__rre/18 177. Lund SK, Quach W, Weissling K, McKelvey M, Dietz A. Assessment with children who need augmentative and alternative communication (AAC): clinical decisions of AAC specialists. Lang Speech Hear Serv Sch. 2017;48(1):56-68. DOI: 10.1044/2016_LSHSS-15-0086 178. Clarke MT, Sargent J, Cooper R, Aberbach G, McLaughlin L, Panesar G, et al. De- velopment and testing of the eye-pointing classification scale for children with cerebral palsy. Disabil Rehabil. 2020:1-6. DOI: 10.1080/09638288.2020.1800834 179. Adamson LB, Bakeman R, Deckner DF. The development of symbol-infused joint engagement. Child Dev. 2004;75(4):1171-87.

59 Acta Universitatis Upsaliensis Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine 1690 Editor: The Dean of the Faculty of Medicine

A doctoral dissertation from the Faculty of Medicine, Uppsala University, is usually a summary of a number of papers. A few copies of the complete dissertation are kept at major Swedish research libraries, while the summary alone is distributed internationally through the series Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine. (Prior to January, 2005, the series was published under the title “Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine”.)

ACTA UNIVERSITATIS UPSALIENSIS Distribution: publications.uu.se UPPSALA urn:nbn:se:uu:diva-421107 2020