Development of an Evidence-Based Clinical Practice Guideline on Linear Growth Measurement of Children1 Jan M

Journal of Pediatric Nursing (2011) 26, 312–324

Development of an Evidence-Based Clinical Practice Guideline on Linear Growth Measurement of Children1 Jan M. Foote DNP, ARNP, CPNP a,b,c,⁎, Linda H. Brady PhD, RN b,c, Amber L. Burke RN, CPN a,b,c, Jennifer S. Cook MD a,b,c, Mary E. Dutcher MS, RD, LD, CDE a,b,c, Kathleen M. Gradoville MA, ARNP, CPNP a,b,c, Jennifer A. Groos MD a,b,c, Kimberly M. Kinkade MSN, ARNP, CFNP a,b,c, Reylon A. Meeks MSN, MS, RN, CPN a,b,c,PamelaJ.MohrRN,CPNa,b,c, Debra S. Schultheis RN, CPN a,b,c, Brenda S. Walker MSN, RNC a,b,c, Kirk T. Phillips PhD, MSW, MS c aBlank Children's Hospital, Des Moines, IA bIowa Health–Des Moines, Des Moines, IA cIowa Health System, Des Moines, IA

Key words: Growth is an important indicator of child health; however, measurements are frequently inaccurate and Linear growth unreliable. This article reviews the literature on linear growth measurement error and describes methods measurement; used to develop and evaluate an evidence-based clinical practice guideline on the measurement of Evidence-based clinical recumbent length and stature of infants, children, and adolescents. Systematic methods were used to practice guideline; identify evidence to answer clinical questions about growth measurement. A multidisciplinary team Growth; critically appraised and synthesized the evidence to develop clinical practice recommendations using an Infants; evidence-based practice rating scheme. The guideline was prospectively evaluated through internal and Children; external reviews and a pilot study to ensure its validity and reliability. Adoption of the clinical practice Adolescents guideline can improve the accuracy and reliability of growth measurement data. © 2011 Elsevier Inc. All rights reserved.

GROWTH IS WELL established as an important and Since impaired or abnormal growth is a common conse- sensitive indicator of health (Hindmarsh & Brook, 1988; quence of a wide range of conditions, its measurement acts Tanner, 1986a, 1986b), and growth monitoring is a as a useful early warning of possible pathology. Linear component of child health care around the globe (De Onis, growth measurements need to be accurate and reliable to be Wijnhoven, & Onyango, 2004b; Grote, Oostdijk, Dekker, of value. Since education alone does not always change Verkerk, & Wit, 2005; Tomkins, 1994; Ulijaszek, 1994). practice, a clinical practice guideline was developed to

1 Identification of previous presentations: Pediatric Endocrinology Nursing Society, Atlanta, GA, April 2010; National Association of Pediatric Nurse Practitioners, Chicago, IL, April 2010; National Evidence-Based Practice Conference, Iowa City, IA, April 2010; Society of Pediatric Nurses, Lake Buena Vista, FL, May 2010; American Academy of Nurse Practitioners, Phoenix, AZ, June 2010; National Primary Care Nurse Practitioner Symposium, Copper Mountain, CO, July 2010; International Pediatric Association Congress of Pediatrics, Johannesburg, South Africa, August 2010. ⁎ Corresponding author: Jan M. Foote, DNP, ARNP, CPNP. E-mail address: [email protected] (J.M. Foote).

0882-5963/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.pedn.2010.09.002 Guideline Development 313 bridge the gap between scientific evidence and clinical Lipman et al. (2000) surveyed 50 primary care practices practice. A goal of this project is to empower clinicians to and found that 78% used inappropriate instruments for examine and improve growth measurement procedures in measuring height and 18% measured children while wearing their own practice settings. shoes. In addition, 88% used inappropriate instruments for measuring length and one practice did not measure children that could not stand alone. More than half of the practices Relevant Literature (58%) had incorrect policies for obtaining height-versus- length measurements. Lipman et al. (2004) performed a study Growth data can lead to the discovery of suboptimal of 55 pediatric and family practices within eight geographical health conditions. These include endocrine disorders, areas of the United States and found that 42% of children nutritional deficiencies, metabolic disturbances, genetic measured standing and 82% of children measured lying were disorders, psychosocial issues, and chronic diseases measured with inappropriate instruments. Spencer, (Ahmed, Allen, Dunger, & Macfarlane, 1995; Alexander Lewando-Hundt, Kaur, Whiting, and Hors (1996) found & Hindmarsh, 2004; Hyer, Cotterill, & Savage, 1995; that 22% of 58 child health clinics in Coventry, UK, did not Vogiatzi & Copeland, 1998; Voss, Mulligan, Betts, & have any height measuring instruments and 76% did not have Wilkin, 1992). Unfortunately, many children are not referred instruments suitable for measuring infants. for evaluation or are referred too late to be treated effectively Measurement instruments are frequently installed impro- (Aynsley Green & Macfarlane, 1983; Jellinek & Hall, 1994; perly and uncalibrated. Voss, Bailey, Cumming, Wilkin, and Lipman & McKnight, 2000) because their growth disorders Betts (1990) checked the calibration of 230 measurement are not recognized. instruments and found that there was a mean error of at least Change in growth over time is more sensitive than a single 1 cm using a 100-cm calibration rod (range 90.0–108.5 cm) in measurement; therefore, the adequacy and appropriateness of all four different types of instruments evaluated. In addition, growth is determined by serial measurements compared with most personnel using these instruments were unaware of the reference standards. Linear growth is a process characterized inaccuracies. Bunting and Weaver (1997) checked the by three distinct phases: infancy, middle childhood, and calibration of height instruments in 12 wards of a children's puberty (Karlberg, 1989; Tanner & Davies, 1985). Infants hospital and 14 outpatient clinics. They found one of six have rapid but decelerating growth of approximately 2.5 cm infant length boards was inaccurate and 12 of 21 stadiometers per month until 6 months old and then 1.25 cm per month were inaccurate by 1 cm or more, with one being inaccurate until 1 year old. Toddlers grow approximately 10 cm by 4 cm. Laing and Rossor (1996) assessed the calibration of between 12 and 24 months (Boom, 2010). Growth velocity instruments in 59 schools. Of the 39 instruments available, varies as children may cross percentile lines on growth charts only 23 (59%) measured within 0.5 cm of a 100-cm rule during the first 2 years of life while they grow toward their (range 98.0–102 cm). genetic potential (Boom, 2010; Rogol, 2009). Children grow In a large growth surveillance study of 20,338 children, approximately 8 cm between 24 and 36 months old and 260 were identified as having heights less than −2 SD approximately 7 cm between 36 and 48 months old (Boom, (approximately less than third percentile); however, mea- 2010). Growth velocity during middle childhood is relatively surement or recording errors were detected among 13.5% of constant at 5 to 7 cm per year. There is often a slight those children (Ahmed et al., 1995). Stoddard, Kubik, and deceleration in growth velocity preceding puberty. Growth Skay (2008) found 20% to 25% of school-based measure- velocity increases during puberty and peaks at 8 to 14 cm per ments taken of 70 children to be unreliable. Lipman et al. year (Kerrigan & Rogol, 1992). (2004) found that 70% of children in 55 primary care Effective growth monitoring requires precise linear practices across the United States were measured using growth measurement, and growth assessments are compro- incorrect techniques. They also found that using appropriate mised without this precision. More than 70 years ago, instruments and training on measurement techniques resulted Meredith (1936) reported that extraordinarily rigorous in an improvement in measurement accuracy (within 0.5 cm) technique is needed to properly measure a child's growth. from 30% to 70%. Tanner (1986a) warned that the heights “measured” in many Diurnal variation in stature was recognized as early as settings are useless for clinical purposes, let alone for 1777 when Count Philibert Guéneau de Montbeillard research. In the 21st century, inaccurate and unreliable linear measured his son at frequent intervals between birth and growth measurements of children are still prevalent pro- 19 years old, providing the oldest longitudinal growth record blems. Sources of measurement error and unreliability in existence (Scammon, 1927). Magnetic resonance imaging include flawed measurement instruments, casual measure- has demonstrated diurnal variation in the fluid volume of ment techniques, diurnal height variation, and the posture intervertebral discs associated with axial loading of the spine and movement of children. Measurement error influences the and gravity results in changes in stature (Boos, Wallin, interpretation of growth patterns and can result in failure to Gbedegbegnon, Aebi, & Boesch, 1993; Keller & Nathan, identify underlying pathology or apparent growth divergence 1999; Roberts, Hogg, Whitehouse, & Dangerfield, 1998). in a normally growing child. Studies have shown that the mean height loss in children 314 J.M. Foote et al. from morning to afternoon or evening can range from 0.47 to comprised of nurses, pediatric and family nurse practitioners, 2.8 cm (Buckler, 1978; Kobayashi, Kobayashi, Tanaka, pediatric and neonatal clinical nurse specialists, nursing Uchiyama, & Togo, 1999; Kobayashi & Togo, 1993; Lampl, educators, a nursing supervisor, a nurse researcher, a pediatric 1992; Rodriguez, Moreno, Sarria, Fleta, & Bueno, 2000; endocrinologist, a primary care pediatrician, and a pediatric Siklar, Sanli, Dallar, & Tanyer, 2005; Strickland & Shearin, dietitian. The nurse researcher had experience in evidence- 1972; Tillmann & Clayton, 2001; Voss & Bailey, 1997). based practice processes and served as a process expert. The Diurnal height changes can lead to misinterpretation of a team members were respected role models and leaders within child's growth velocity when measured at different times of theirowndisciplineswhosharedaninterestingrowthas- the day for serial encounters. After Whitehouse, Tanner, & sessment and evidence-based practice. Together, they repre- Healy (1974) suggested that applying gentle upward pressure sented the views of practice, research, education, and on the mastoid processes during measurement could administrative stakeholders, as well as intended guideline minimize the effects of diurnal variation, some clinicians users. The team met once or twice a month over a 1-year period, adopted a controversial stretching technique. with team members having assignments between meetings. Voss et al. (1990) examined what variance in height measurement was attributable to the subject. Under blind and randomized conditions, the standard deviation of a single Scope of the Clinical Practice Guideline height measurement was generally between 0.2 and 0.3 cm, and over 95% of the variance was attributable to the Focused clinical questions drive the evidence-based movement of the child. Ahmed, Yudkin, Macfarlane, practice process. A foreground question was developed for McPherson, & Dunger (1990) studied height measurements this project using four components, termed PICO (an in young children performed by health visitors using simple acronym for patient/population/problem, intervention/expo- instruments and found that the proportion of total variance sure of interest, comparison of intervention or measure, and attributable to the child ranged from 29% to 51%. In a outcome) (Nollan, Fineout-Overholt, & Stephenson, 2005). longitudinal study of infant growth, 925 replicate measure- The PICO question for this project was: “What are the best ments of recumbent length of three infants by the same instruments and techniques (comparison) to measure (inter- researcher and an assistant identified that 60% to 70% of the vention) the linear growth (outcome) of children (popula- measurement unreliability was due to child factors (Lampl, tion)?” This overall question was divided into eight specific Birch, Picciano, Johnson, & Frongillo, 2001). They and searchable clinical questions to be answered by the most suggested that temperament and level of resistance, muscle relevant and best evidence. tension related to fatigue or high activity levels, and endogenous factors such as hydration and the growth process • What instruments will measure the length of children itself may influence the degree of measurement error. Since a accurately and reliably? living subject does not have a fixed height or length, this has • What instruments will measure the height of children implications for whether a child should be measured once or accurately and reliably? multiple times during a single encounter to obtain a • Can less expensive instruments measure children's measurement closest to the true value. length and height accurately and reliably? After defining the challenges of linear growth measure- • How often should measurement instruments be calibrated? ment, a preliminary review of literature on measurement • What techniques will measure the length of children instruments and techniques was completed before proceed- accurately and reliably? ing with the guideline's development. No existing evidence- • What techniques will measure the height of children based guidelines on linear growth measurement instruments accurately and reliably? and techniques were identified; however, it was determined • How should practitioners address the diurnal variation that there was a body of scientific evidence available to in height? formulate an evidence-based clinical practice guideline. The • How many times should a child be measured at each AGREE Instrument, a framework for assessing the quality of encounter? clinical practice guidelines, was selected as a guide to ensure a structured and rigorous guideline methodology was The purpose of the clinical practice guideline is to assist followed. (The AGREE Collaboration, 2001). health professionals in applying evidence-based knowledge to the process of measuring linear growth in infants, children, and adolescents using standardized instruments and techni- Guideline Development Team ques. The intended guideline users are nurses, nurse practitioners, clinical nurse specialists, physicians, physician A pediatric nurse practitioner served as project director assistants, dietitians, allied health personnel, and other health (J.M.F.) and organized a 12-member multidisciplinary team care providers who practice in pediatric and family practice of health professionals with varied expertise and perspectives primary care, pediatric specialties, hospitals, schools, and to develop the clinical practice guideline. The team was community health settings. Guideline users should be able to Guideline Development 315 implement accurate and reliable techniques for measuring ments about the quality of evidence among reviewers were recumbent length and stature using appropriate instruments reconciled by consensus among the team members. in their own practice settings. Once all of the literature had been reviewed, the The guideline excludes other anthropometric measure- evidence was organized according to the eight specific ments (e.g., weight, head circumference, segmental lengths), clinical questions. The aggregate body of evidence was the use of growth charts, and the interpretation of growth then synthesized and used to formulate explicit clinical patterns. Although measuring weight is not included in the practice recommendation statements. The strength of guideline, it should be noted that accurate measurements of evidence supporting each recommendation was graded both growth and weight are necessary to calculate an according to modified USPSTF (1996) Evidence-Based accurate body mass index (in children aged 2 years and Practice Ratings (Table 1). older) and weight per length (in infants and younger children), which are important indicators of overweight and obesity. The guideline does not include recommendations for Internal and External Reviews when or how often to measure growth in various settings. However, the American Academy of Pediatrics has recom- The drafted guideline was internally reviewed by several mended a schedule of growth measurements for preventive stakeholder groups including a pediatric nurse practitioner, a pediatric health care (Hagan, Shaw, & Duncan, 2008). neonatal nurse practitioner, a family nurse practitioner, two pediatricians, a neonatologist, an adolescent medicine physician, two pediatric endocrinologists, two pediatric Search Strategy inpatient nurse managers, two pediatric unit-based nurse educators, and five members of the organization's multidis- Terms derived from the clinical questions were used by ciplinary Evidence-Based Practice Committee. The guideline the project director and a health sciences librarian to search was reviewed externally by nine experts from the Pediatric these databases: COCHRANE, MEDLINE, CINAHL, Endocrinology Nursing Society Research Committee who EMBASE, OCLC, and ERIC. Additional studies and were chosen for their scientific and clinical expertise in alternative literature were identified through the mining of children's growth. To provide consumer stakeholder input, article reference lists, contact with experts in the field, the guideline was also reviewed by five parent representatives anthropometric and endocrinology textbooks, and informal discovery. Secondary searches were performed throughout the project to identify gaps in the literature and near the Table 1 U.S. Preventive Services Task Force Evidence-Based completion of the guideline to identify any new literature Practice Ratings that had been published during the course of the project. Quality of Evidence I. Evidence obtained from at least one properly randomized Data Extraction and Quality Assessment controlled trial. II-1. Evidence obtained from well-designed controlled trials The project director reviewed the candidate literature, without randomization. with the assistance of a second team member when II-2. Evidence obtained from well-designed cohort or case- necessary, for pertinence to at least one of the clinical control analytic studies preferably from more than one center or research group. questions to determine what should receive a full review. II-3. Evidence obtained from multiple time series with or Each full-text article was critiqued by the project director without the intervention. Dramatic results in uncontrolled and several team members to minimize the risk of bias. experiments could also be regarded as this type of evidence. Literature not available in English was excluded, but no III. Opinions of respected authorities, based on clinical limits were established on the publication dates. The experience; descriptive studies and case reports; or reports of guideline includes 128 references that were used in its expert committees. development, while more than 200 were excluded because they did not provide relevant or sufficient evidence to answer Strength of Recommendations (Modified) the selected clinical questions. A. There is good evidence to support the recommendation. Forms modified from a toolkit for promoting evidence- B. There is fair evidence to support the recommendation. based practice (Titler, 2002) were used to critique the research C. There is insufficient evidence to recommend for or against, articles and summarize the non-research literature. The but recommendations may be made on other grounds. research critiques and literature summaries were discussed D. There is fair evidence to support exclusion of the practice. at guideline development team meetings. The quality of E. There is good evidence to support exclusion of the practice. evidence from each individual article was rated according to Note: Data from USPSTF (1996). Guide to clinical preventive services: the U.S. Preventive Services Task Force (USPSTF, 1996) Report of the U.S. Preventive Services Task Force (2nd. Ed.). Evidence-Based Practice Ratings (Table 1). Any disagree- Philadelphia: Lippincott, Williams & Wilkins. 316 J.M. Foote et al. from The Magic Foundation (2010) (Major Aspects growth of children and to standardize the staff members' of Growth In Children), a nonprofit organization that pro- practice to the procedures outlined in the guideline. The in- vides support services for the families of children affected service was developed using Rogers' (1995) diffusion of with a wide variety of chronic and/or critical disorders, syn- innovation theory, conveying three types of relevant dromes, and diseases that affect childhood growth. The knowledge. Awareness knowledge was promoted through internal and external reviews were essential to ensure that the conveying the importance of growth monitoring in children guideline was valid, clear, and practical and that recommen- and evidence-based practice. They were provided “how-to” dations could be implemented in a manner likely to influence knowledge for improving their measurement practices by clinical practice. reviewing the guideline step-by-step, graphical depictions of proper instruments and positioning of children, and the opportunity for demonstration and return demonstration of Pilot Study techniques. The principle knowledge or the “why” was conveyed by discussing the scientific rationale for each Following approval by the appropriate institutional clinical practice recommendation. The staff members were review boards, a pilot study was conducted in a pediatric asked to follow the guideline's techniques for measuring clinic that includes primary and specialty care. The primary infants, children, and adolescents in their practices. Posters purpose of this descriptive study was to ensure that the of the basic steps of the guideline, graphics showing proper guideline was easy to understand and practical to implement. positioning of the child during measurement, and a list of A secondary purpose was to collect preliminary data on common measurement errors were placed next to the reliability and measurement variability. The pilot study measurement instruments in the clinic areas. consisted of educating staff members and then collecting After using the guideline for 6 weeks, all 16 staff data about the guideline's clarity, applicability, and feasibi- members were surveyed about the clarity, applicability, and lity; spot checking and correcting existing measurement feasibility of the clinical practice guideline. Using a four- instruments; and determining intraexaminer and interexami- point Likert scale, they agreed or strongly agreed with all the ner measurement reliability and variability. statements in Table 2. They found the guideline to be Without prior warning, existing measurement instruments understandable and the clinical practice recommendations to were evaluated by two observers for proper calibration and be logical and reasonable. Use of the guideline gave them necessary components (according to the guideline) using more confidence in the accuracy of their measurements, and Perspective Enterprises calibration rods, a standard non- they would recommend use of the guideline to others. stretchable tape measure, a Johnson magnetic angle locator A convenience sample of children was measured to no. 700, and a Macklanburg–Duncan top reading magnetic determine intraexaminer and interexaminer reliability, with torpedo level. A 100.0-cm aluminum rod was used to check the consent of their parents or guardians. These children were the accuracy of installation of seven height measuring attending appointments for health maintenance visits, acute devices (one Harpenden & Holtain 602VR, five less illnesses, and chronic diseases. Thirty-five infants and young expensive Accustat measuring devices, and one steel tape children (aged 4 days to 30 months 1 week; 17 girls and 18 measure mounted to the wall between two strips of wood), boys) had their lengths measured on one of three different and a 60.0-cm aluminum rod was used to check the accuracy length boards (two Ellard length boards PED LB 35-107-X of four length boards (all of which were length and weight and one Perspective Enterprises Easy-Glide Bearing Infant- combination units). The recorded length of the rod was based ometer PE-RILB-BRG2) by one of eight staff members and on the mean of two readings. The range of error was least for the expert (project director). Thirty-seven children and stadiometers (−0.2 to 0.3 cm) and greatest for length boards adolescents (aged 2 years 6 months to 17 years 6 months; (−5.1 to 0.3 cm). The instruments were subsequently 19 girls and 18 boys) had their heights measured on one of repaired, modified, or replaced as necessary and calibrated five different stadiometers (one Harpenden & Holtain appropriately to comply with the guideline. 602VR, one Perspective Enterprises Easy-Glide Bearing Sixteen staff members (eight registered nurses, one Stadiometer PE-WM-60-76-BRG, and three Accustats) by 1 licensed practical nurse, one registered dietitian, and six of 11 staff members and the expert. They were measured on allied health personnel), who were intended guideline users, accurately installed and calibrated instruments under stan- were educated on the clinical practice guideline during a dard clinical conditions in nonblind and successive order. 1-hour in-service. The staff members had 8 months to 42 They were each measured to the last completed millimeter years experience in measuring children and measured 1 to three times by a staff member and three times by the expert. 150 children per week. The project director, who had 18 Parents and guardians acted as assistant measurers for the years of experience in educating health professionals and infants and young children in whom length was measured allied health personnel about anthropometric measurements, because a second health professional is not routinely taught the in-service to these potential guideline users. The available in many clinical settings. The instruments were goals of the in-service were to promote the concept of checked for calibration throughout the pilot study, and none evidence-based practice over tradition in measuring the required adjustment. Guideline Development 317

Table 2 Guideline User Survey (n = 16): Frequency of Likert Responses by Item Strongly Agree Agree Disagree Strongly Disagree (4) (3) (2) (1) M Score 1. Growth is a sensitive indicator of health in children. 81.25% (13) 18.75% (3) 0 0 3.81 2. The clinical practice guideline is applicable to my practice. 68.75% (11) 31.25% (5) 0 0 3.69 3. The recommendations are clear and understandable. 81.25% (13) 18.75% (3) 0 0 3.81 4. I can identify appropriate and inappropriate measurement 62.5% (10) 37.5% (6) 0 0 3.63 instruments. 5. I can identify appropriate and inappropriate 62.5% (10) 37.5% (6) 0 0 3.63 measurement techniques. 6. I can identify common errors in measuring children. 62.5% (10) 37.5% (6) 0 0 3.63 7. Clinical practice recommendations are linked with 56.25% (9) 43.75% (7) 0 0 3.56 scientific evidence and rationale. 8. Rationale for each recommendation is logical and 62.5% (10) 37.5% (6) 0 0 3.63 reasonable. 9. The key recommendations are easily identifiable. 66.67% (10) 33.33% (5) 0 0 3.67 10. The modifications for special situations are 62.5% (10) 37.5% (6) 0 0 3.63 understandable. 11. I have more confidence in the accuracy of my 56.25% (9) 43.75% (7) 0 0 3.56 measurements. 12. Patient care will be enhanced by improved 68.75% (11) 31.25% (5) 0 0 3.69 measurement accuracy & reliability. 13. I would recommend use of this clinical practice 62.5% (10) 37.5% (6) 0 0 3.63 guideline to others. 14. Use of this guideline should be a competency for those 53.33% (8) 46.67% (7) 0 0 3.67 who measure children. Total scores 3.66

There were no significant differences between the measurements, and the mean of the all three measurements. reliability results of individual staff members or types of A majority of repeated measurements within and between instruments used to measure the children, and consequently, examiners were within 0.3 cm and nearly all were within the values for length measurements and the values for height 0.5 cm. This degree of precision is recommended because measurements were each pooled. Table 3 shows the errors can be magnified over the course of serial growth reliability of measurements taken by the same examiner monitoring, leading to misinterpretation of growth patterns. was greater than .99 for length and height measurements for Based on normal growth velocities per age, larger measure- both the staff and the expert (p b .0001). Table 4 shows the ment errors are clinically intolerable. reliability of length and height measurements taken by The range of differences between the three length different examiners was also greater than .99 for single measurements was 0 to 1.1 cm (M 0.39 cm) for the staff measurements, the mean of the first two measurements, and and 0 to 0.4 cm (M 0.17 cm) for the expert. The range of the mean of all three measurements for both length and differences among the three height measurements was 0.1 to height (p b .0001). 0.5 cm (M 0.24 cm) for the staff and 0 to 0.3 cm (M 0.13 cm) All measurements have intrinsic variability or precision for the expert. The range of differences between three error when repeated because living subjects do not have fixed heights/lengths. Measuring subjects more than once and using the mean can reduce the effects of measurement Table 3 Intraexaminer Reliability: Comparison of Repeated error. For quality assurance purposes, there must be a set Length and Height Measurements (First, Second, and Third) limit of agreement between repeated measurements, such as Taken by the Same Examiner (Staff or Expert) 0.3 to 0.5 cm. Table 5 shows the variation in length and Measurement 1 vs. 2 1 vs. 3 2 vs. 3 height measurements taken by the same examiner as percentage of differences within 0.3 cm and within 0.5 cm Length (n = 35) between the first two measurements and between all three Staff .99970 .99918 .99961 measurements for the staff and for the expert. Table 6 shows Expert .99990 .99993 .99993 Height (n = 37) the variation in length and height measurements taken by Staff .99997 .99995 .99996 different examiners as the percentage of differences within Expert .99998 .99999 .99999 0.3 cm and within 0.5 cm between the staff's and the expert's b single or first measurements, the mean of the first two Note: Reliability estimates are Pearson correlation coefficients (p .0001). 318 J.M. Foote et al.

Table 4 Interexaminer Reliability: Comparison of Length and Table 6 Interexaminer Measurement Variability: Percentage Height Measurements (First, Mean of First Two, and Mean of of Length and Height Measurements (First, Mean of First All Three) Taken by Different Examiners (Staff and Expert) Two, and Mean of All Three) Taken by Different Examiners (Staff and Expert) That Varied by ≤0.3 and ≤0.5 cm Measurement 1 M1+2 M1+2+3 Length (n = 35) .99981 .99990 .99983 Measurement 1 M1+2 M1+2+3 Height (n = 37) .99997 .99999 .99998 Length (n = 35) ≤ Note: Reliability estimates are Pearson correlation coefficients (p b .0001). % differences 0.3 cm 91.4 97.1 91.4 % differences ≤0.5 cm 100 100 94.3 Height (n = 37) measurements showed that precision was greater for height % differences ≤0.3 cm 91.9 94.6 94.6 than for length. % differences ≤0.5 cm 94.6 97.3 100 The pilot study demonstrated that using the guideline to measure the recumbent length and stature of children can result in strong intraexaminer and interexaminer reliability. Internal and external reviewers, as well as guideline users Single measurements did not compare as well as the mean in the pilot study, were asked to identify barriers to of two or more measurements (p b .001), providing implementing the clinical practice guideline. Potential additional evidence for measuring children more than once barriers included lack of awareness of the guideline itself during each encounter. Overall, pilot study results were as well as the scientific evidence supporting its recommen- comparable to previously reported studies with acceptable dations, unfamiliarity with terms, lack of appropriate and levels of reliability and measurement variability (De Onis calibrated measurement instruments, forgetting or neglect- et al. 2004a; Gordon, Chumlea, & Roche, 1991; Roche & ing important steps of the measurement procedures, the need Sun, 2003; Tanner & Whitehouse, 1982; Ulijaszek & Kerr, to make modifications for special situations, adherence to the 1999; Ulijaszek & Lourie, 1994; WHO Multicentre Growth guideline, and sustaining practice changes. Awareness of Reference Study Group, 2006). Most importantly, the barriers to practice change helps with tailoring knowledge guideline users found the clinical practice guideline to be translation interventions (Straus, Tetroe, & Graham, 2009). clear, applicable, and feasible to implement. Analyses of data from the reviews and the pilot study were used by the guideline development team to improve and finalize the guideline and to tailor implementation tools. The Results evidence-based clinical practice guideline provides clinical practice recommendations for measurement instruments, The best evidence was critically evaluated to answer measurement techniques, use of less expensive instruments, clinical questions about measuring recumbent length and calibration of instruments, when to measure length versus stature of infants, children, and adolescents. There was height, diurnal height variation, and replicate measurements. strong evidence for most of the major clinical practice Graded recommendations are linked with scientific rationale recommendations. Expert opinion was included as an and supporting references (refer to Table 7 for a short excerpt adjunct to other evidence and where good evidence was from a section of the guideline). Modifications for special lacking. Prospective evaluation of the guideline was circumstances (e.g., obesity, genu valgum, leg length conducted through internal and external reviews including asymmetry, and scoliosis) are provided. Although using expert reviews, as well as a pilot study that was conducted alternative methods to measure children with special needs under standard clinical practice conditions. was not within the scope of the project, some recommendations with references are provided in the guideline. The clinical practice guideline and implementation tools are available at the Blank Children's Hospital Web site Table 5 Intraexaminer Measurement Variability: Percentage (http://www.blankchildrens.org/linear-growth-measurement. of Length and Height Measurements (First Two and All Three) aspx) and through the National Guideline Clearinghouse Taken by the Same Examiner (Staff or Expert) That Varied by (http://www.guideline.gov). The guideline is also being ≤ ≤ 0.3 and 0.5 cm disseminated through educational presentations to a variety Staff Expert of national and international audiences. Implementation tools Measurement 1+2 1+2+3 1+2 1+2+3 include a glossary of terms, lists of common errors in measuring length and height, a sample instrument calibration Length (n = 35) log, an audit tool to measure ongoing adherence, and a list of % differences ≤0.3 cm 82.9 51.4 97.1 97.1 % differences ≤0.5 cm 100 82.9 100 100 sources for measurement instruments. Posters on length and Height (n = 37) height measurement procedures with graphics that show % differences ≤0.3 cm 91.9 67.6 100 100 proper positioning of children (Figures 1 and 2, respectively) % differences ≤0.5 cm 100 100 100 100 are also available to facilitate implementation of the guideline. Placing these posters in the measurement areas Guideline Development 319

Table 7 Example of Clinical Practice Recommendation and Scientific Rationale Two measurers are required to obtain a Correct positioning cannot be accomplished without two people. Length measurements length measurement. (level of evidence: A) taken by two measurers results in improved intraexaminer and interexaminer reliability (Chang, Robson, & Spencer, 1993; Davies & Holding, 1972; De Onis et al., 2004a; Doull, McCaughey, Bailey, & Betts, 1995; Gordon et al., 1991; Lampl, 1993; Lampl et al., 2001; Lampl, Veldhuis, & Johnson, 1992; Lawn, Chavasse, Booth, Angeles, & Weir, 2004; Roche & Sun, 2003; WHO Multicentre Growth Reference Study Group, 2006) compared with measurements taken by a single measurer (Colley, Tremble, Henson, & Cole, 1991; Corkins, Lewis, Cruse, Gupta, & Fitzgerald, 2002; Johnson & Engstrom, 2002; Johnson, Engstrom, & Gelhar, 1997; Johnson, Engstrom, Haney, & Mulcrone, 1999; Johnson, Engstrom, Warda, Kabat, & Peters, 1998; Miller & Hassanein, 1971; Rosenberg, Verzo, Engstrom, Kavanaugh, & Meier, 1992; Shinwell & Shlomo, 2003; Smith, Newcombe, Coggins, & Gray, 1985) of practice settings informs patients and families as well and educational sessions and/or demonstrated competency on can help engage them in proper measurement procedures. an annual basis for health care personnel who measure children. Additional refresher sessions should occur when a lack of standardization is observed. Limitations The guideline development team assumes that health professionals will use their clinical knowledge and judgment Some studies and review articles used in the development in applying the guideline's clinical practice recommendations of this guideline were historical in nature; however, they to the measurement of individual children in their own were relevant and of good quality. Many of the studies were practices. Health care decisions regarding children's growth descriptive and there were few randomized controlled trials should be based upon accurate and reliable measurements due to the nature of the topic. Some of the studies cited were using appropriate instruments and techniques rather than on conducted for purposes other than determining measurement casual techniques using flawed instruments. Adoption of reliability, but they reported the reliability data for their this guideline will provide practitioners and parents with measurement instruments and/or techniques. accurate and reliable information about children's growth. Baseline data on measurement reliability was not obtained Accurate growth assessments are necessary to recognize, in the pilot study; however, there is sufficient evidence from diagnose, and treat growth disorders and other pathology in a other studies that measurements are frequently inaccurate timely manner, as well as to avoid unnecessary referrals and and unreliable when using faulty instruments and non- costly evaluations in children with normal growth. standardized techniques. Other limitations of the study Growth measurement is a relatively inexpensive method include lack of power analysis, the small sample size of of monitoring and improving child health. Sources for children, and the fact that staff member participants were measurement instruments, including some less expensive employed in the organization where the guideline was models, are included with the guideline. A systematic review developed. The Hawthorne effect may have been a factor in supported the utility and cost effectiveness of growth the results of the pilot study since the staff members knew monitoring to increase the detection of stature-related that their measurements were being studied. The staff disorders (Fayter et al., 2008). Cernerud and Edding (1994) members read their own measurements, as is done routinely also found that investment costs and running expenses of in clinical situations. They were reminded that some variance growth surveillance were very low. They noted additional is expected to offset any attempts to obtain replicate benefits to measuring growth including discussions with measures of expected values. Technical errors of measure- children and their parents about growth and what is normal, ment were not reported due to the measurements being reassurance of adolescents about their developing identity performed at different times with different instruments. and body image, the revealing of conditions such as maltreatment during the measurement procedure, and the Implications for Practice use of growth data in the field of public health research.

A recurring theme in the literature review was the importance of regular education sessions for staff. Educating Implications for Research and Evidence-Based staff to measure the growth of children properly is one step Practice Projects toward ensuring quality health care. In the pilot study, there was agreement among staff members that the guideline During the process of reviewing the literature and should be a competency for those who measure children's developing the guideline, the team identified several areas growth. The guideline development team recommends for further research. It would be beneficial to conduct 320 J.M. Foote et al.

Figure 1 Blank Children's Hospital's poster on length measurement procedures showing proper positioning of children. Guideline Development 321

Figure 2 Blank Children's Hospital's poster on height measurement procedures showing proper positioning of children. 322 J.M. Foote et al. additional research on linear growth measurement with Moines Evidence-Based Practice Committee and Blank randomized controlled trials and other studies using Children's Hospital; the Variety Club John R. Grubb experimental designs. More studies should address measur- Children's Health Center and the pilot study participants; ing children with special health care needs and measuring Paula Whannell, MA, BSN, RN, Health Sciences Librarian premature infants inside and outside of the incubator. Studies and the Iowa Health–Des Moines Health Sciences Library; should be designed and reported using methods that allow for The University of Iowa College of Nursing faculty: Patricia comparison of measurement error and reliability. Clinton, PhD, RN, CPNP; Brenda Hoskins, DNP, RN, GNP- The clinical practice guideline should be implemented BC; Charmaine Kleiber, PhD, RN, CPNP; Rebecca Siewert, and evaluated in diverse clinical settings. Evidence-based DNP, RNC, NNP. This project was supported in part by a guidelines are needed for performing other types of grant from the Pediatric Endocrinology Nursing Society. anthropometric measurements, as well as monitoring and interpreting childhood growth patterns. The guideline will be updated within 5 years, or sooner depending upon the emergence of new scientific evidence. References

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