Catita et al. Philosophy, Ethics, and Humanities in (2020) 15:3 https://doi.org/10.1186/s13010-020-00087-2

REVIEW Open Access Normality in medicine: a critical review Marisa Catita1,2, Artur Águas2 and Pedro Morgado1,3*

Abstract

What is considered normal determines clinical practice in medicine and has implications at an individual level, doctor-patient relationship and health care policies. With the increase in medical information and technical abilities it is urgent to have a clear concept of normality in medicine so that crucial discussions can be held with unequivocal terms. The different meanings for normality were analyzed throughout the literature and grouped according to their relevance in the academic community in models, namely the Biostatistical Theory (BST), Health, Ideal, Process and Biological advantage. The BST is the most established naturalistic approach, however normal variability can arguably constitute a problem. Health is similar and raises the question of setting the boundaries of . Normality as an Ideal is an useful tool but is naturally unrealistic. As a Process it is comprehensible but is hard to frame for practical purposes. If considered as a Biological Advantage, seems intuitive but abnormality should tend to disappear. After, three examples were presented to discuss these models. They were Anemia, Psychiatric diseases and Psychopathy. In the case of Anemia the BST was applied and the arbitrary boundaries but with social impact were exposed. Psychiatric diseases was discussed under the process of self-organization and non-suffering ideal. With Psychopathy the boundaries of biological advantage are questioned. This review appeals to the importance of redesigning of the concept of normality in medicine according to current times and stresses the importance of integrating concepts such as variability and autonomy. Keywords: Normality, Medical ethics, Cultural medicine,

Abreviations BST Biostatistical Theory. disease, with implications from the patient self- DSM Diagnostic and Statistical Manual of Mental perception and doctor-patient communication, to the Disorders. goal of medical intervention, health insurance policies Hb blood hemoglobin concentration. and public health measures [2, 8, 9, 14]. The prolifera- Hct hematocrit. tion of medical information, which is at the general pub- HDA Harmful dysfunction analysis. lic disposal, and the technological possibilities should HST Holistic Theory of Health. keep pace with conceptual and ethical literacy. Alarming WHO World Health Organization. interpretations proliferate to the detriment of a balanced relationship with health issues. Diagnostics and thera- Introduction peutics to achieve a given normality cause public in- In clinical practice normality is at the basis of all com- stability worth attention, since this changing nature of parisons. [7] From normality derives both health and health is unavoidable and normalizing parameters is not a solution to a balanced approach to life. Since there are * Correspondence: [email protected] tools to alter conditions the main focus should be in de- 1 Life and Health Sciences Research Institute (ICVS), School of Medicine, fining when to intervene. University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal 3ICVS-3Bs PT Government Associate Laboratory, Braga/Guimarães, Portugal Full list of author information is available at the end of the article

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Medicine is said to be the most humane of sciences Normality models and the most scientific of humanities. As a science Normality has no consensual definition in medical litera- striving for its objectivity and as a humanity in search ture. Not only the meaning varies, but also does the way of understanding, the concepts that lay the foundation it is conceptualized. In a simplistic view, it can have a for medicine must be clearly defined [2]. With the naturalistic or normative approach [9]. The former tries varietyofsubjectswherethetermnormalityisap- to identify what the term means for the ones who apply plied, and with different meanings, misunderstandings it, independent of value judgments. The normative as a occur easily. more constructive intention, where the meaning is Philosophers of medicine regard normality either dir- established by the theorists [6]. ectly or indirectly along with the concept of health and From the articles studied were chosen the models that disease. In the first place, the foundations for the theory stood out as more relevant, for the strength of their ar- of medicine must be considered. guments and their popularity amidst scholars. They con- Historically, Plato and Aristotle convey that medi- stitute oversimplifications to help clarify each abstract cine produces health. Plato understood health in a rationalization and along this path they sometimes over- hierarchical order, whereby health would mean the lap each other. supremacy of the soul over the body, and thus the ra- tional part would surpass the desirous one [10]. From Biostatistical theory (BST) Aristotle’s view that motion is an actualization of a The BST of health, is a well-established naturalistic ana- potentiality, health can be interpreted as the ability to lysis by Christopher Boorse, discussed and revised since accomplish goals, being healthier the one with more the seventies [2]. According to it health is synonym of options or possibilities [10]. normality, and represents the total absence of patho- Modern medicine arises in the nineteenth century, and logical conditions [2]. according to Canguilhem and Foulcaut point of view, it In brief, health is normal functional ability for a mem- is a product of two revolutionary changes in the clinical ber of the reference class. This normal function refers to orientation that organized the theory of medicine into a statistically typical contribution by a part or process to ontological and physiological [3]. The ontological was their individual survival [or] reproduction. The reference the endeavor to correlate anatomic pathology to clinical class is determined by the age group and sex, translating . Then physiology brought an an uniform functional design. A pathological condition experimentally-based medicine, as by the 1820s Brous- is then the internal state in which these normal func- sais observed that the normal and pathological could be tions are impaired below the typical efficiency [2]. a matter of different intensity, in a quantifiable function This theory unifies multiple concepts, some of them with continuous values [3, 9, 14]. Pasteur in the mid discussed below, and is adequate for many practical con- nineteenth century with his experimental work on the texts, being its main advantages its naturalistic and germ theory fits the ontological conception, whereas in quantifiable approach, both important to attain objectiv- the 20 century the French and German reductionist ity and fairness. Since this theory is comprehensive and schools were prone to quantify physiological processes the author did several publications and adaptations in [14]. rebuttal to many of the critics, it is cherished for its co- Also worth noticing is the impact from the model of hesion and for allowing vigorous debate [2]. biological order and function that Darwin brought with On the other hand, the simple fact that this definition the publication On the Origin of Species, postulating an would mean that an individual is only normal when ever-changing species which can be extrapolated to such healthy and that an individual with any disease is abnor- subjects as immunology [14]. mal is something to bear in mind regarding its implica- Among the most prominent theorists in contemporary tions for the societal views on disease. philosophy of medicine are Christopher Boorse for his As Koeslag points out, normal is associated with usual Biostatistical Theory of Health, and Georges Canguilhem [7]. This means that no matter what function is mea- who is frequently cited for his conception of health as a sured, the same proportion of asymptomatic individuals dynamic state of changing norms. would be considered outside the range of normal (5% is The literature on the conceptualization of normality in the value used by default), and the subnormal tail con- medicine was analyzed through this revision with a view sidered diseased by Boorse. With 10 independent tests to better understand the models suggested thus far, what for different functions, the probability of having at least are their advantages and disadvantages in terms of how one extra-normal value is of 42%, whereas if 25 tests are they fit current usage and how they promote adequate done, the chance is of 75%. Inversely, all diseases would communication and subsequent decisions. No patients have the same frequency [7]. These are of course major were involved in this work. limitations to the use of a biostatistical approach since it Catita et al. Philosophy, Ethics, and Humanities in Medicine (2020) 15:3 Page 3 of 6

has no good integration of variation and simple Process polymorphism. According to Canguilhem, who contrasts between the normal and pathological instead of health and disease, normality is a process and reflects the ability to adapt to Health a certain context, internal and external [9]. The organ- Normality understood as health is a prevalent view in ism structures these environments, rather than submit- medical philosophy. The terms are used interchangeably ting to them. There is self-organizatio n[14]. Individuals [7]. Different philosophers give some nuances to the make their own decisions regarding what they consider conception of health, which can be either classified as best for their life [12]. Note that in this model normality naturalistic or normative. is neither statistical nor the absence of disease [12]. Nordenfelt presents a definition for health in his Hol- Normality as a process has the advantage of integrat- istic Theory of Health (HST), that identifies health with ing variability. Rudnick proposes that certain the ability to reach vital goals in standard circumstances are so common in one’s life that they can be interpreted [13]. Wakefield presents the harmful dysfunction ana- as normal variants [9]. These can be fully compensated lysis (HDA), adding that part-dysfunction is not suffi- by mechanisms of self-organization where alternatives cient for considering a given condition a disease [15]. are found to the disrupted structures and functions. On a social scale defining the expectations of what is From this perspective presents itself as patho- normal determines, for example, insurance coverage logical only when self-organization is impaired and there [14]. Even if health has not a clear definition, the promo- is a resulting handicap [9]. This view goes along with tion of health is generally seen as the goal of clinical normality seen as the end of medical intervention since medicine [13]. while medical technologies aim to prevent and treat dis- According to Wakefield, with the HDA, being value eases they also modify what is considered normal [12]. laden is necessary for analyzing the foundations of a If normality is seen as a process than there is an inher- practical activity like medicine versus a pure science, ent continuity associated with it. This implies drawing a therefore this is an sine qua non condition for any con- line between health and disease that is inevitably some- ception of normality as health [15]. This is in conflict what arbitrary [11]. However, it cannot be reduced to an with the naturalistic approach suggested by Boorse [2]. arbitrary subjective preference since the aimed outcome Nordenfelt defends that health is not normality inas- is the adaptation to the context [12]. Additionally, it can much conditions are not diseases because they are ab- be harder to apply in legal contexts. Healthcare justice normal. Cancer is not a disease because it is abnormal entails that disease inhibits equality of opportunity and but because it entails physiological dysfunctions [13]. that public health efforts should create mechanisms to Noting that incidental cases of flu are normal, but not protect it [11]. healthy, health can be regarded as a special case of nor- mality [9]. This leads to the preeminent challenge of de- marcating between the normal and the pathological. Biological advantage Medicine and biology are affiliated, and their concepts Ideal intertwined. Darwin’s theory of natural selection is one Vesalius depicted an anatomy that no living human be- of the most important concepts of biology and it states ing has. The reductions that these depictions entail is of that inherited variations that increase the individual’s major didactic importance. Additionally, medical inter- ability to compete, survive and reproduce are what vention entails objectives to be attained [9]. Simplifica- drives evolution. This is a naturalistic approach that dis- tions are an essential undertaking when complex misses the formulation of a theoretical meaning. The matters are operated since the reduction to categories al- analogy with normality in humans is that functions that lows actions to be taken [11]. It allows the formulation don’t promote the purpose of evolution would be abnor- of guidelines, decision algorithms, and hence can also mal. Immunology is an example of the extension of this have legal functions. This is a naturalistic model of nor- biological advantage model. In its principles the self is mality since determination of ideal proprieties is defined not a given entity, but rather it is a result of identifying by optimal function and not by personal judgement. the self and of the dynamic interaction with the external On the other hand, this ideal attribute has no inde- and adapts to it, being the best adaptation the one which pendent meaning. Nothing can be universally optimal. strives [14]. The best to a function might act in the detriment of This model key feature is it universality, since it ap- other [7]. These are elusive expectations embedded in plies the concept of normality to the human species as it collective consciousness that are in truth unrealistic de- would to any other [14]. Another aspect is the suitability mands [14]. to theories of the mind [14]. Catita et al. Philosophy, Ethics, and Humanities in Medicine (2020) 15:3 Page 4 of 6

However if both the self and the environment are diagnostic of mental illnesses, and its validity is continu- changing, so does the delineation of what constitutes a ously questioned. Whether mental illnesses are normal biological advantage [14]. If evolution is an ongoing or not is a matter requiring serious analysis in a world process human functions would vary in their aim where stigma and industry rule. The boundaries that de- throughout history and normality could only be de- termine whether someone is simply being human and scribed linked to a period in time [7]. complex or on the other hand alarmingly dysfunctional Another problem is that natural selection is a central in need for serious therapy are blurry. mechanism in evolution and the best adaptation prevails, Obsessive-compulsive behaviors can be a motive for the analogy to health would mean that a reduction in pride and success for some and a living nightmare for pathology rates over time would be expected, even with- others. Their own perception of having a problem so out medicine, which is not true [9]. often is the criteria for having it. Using the normality as Health framework, some of these repetitive behaviors Examples could be seen as normal if not experienced as dysfunc- Bearing in mind these models the next section will com- tional and/or inducing psychological suffering. prise some examples, where the goal is to understand Discussed in the light of the Process framework, nor- how certain entities can be analyzed in terms of mality would be conceptually achieved tackling either normality. the disfunction itself or the self-organization the subject has around it. In other words, this level of subjectivity Anemia suggests that either the doctor helps with changing the According to World Health Organization (WHO) cri- obsession, or, why not, rather changing the perception teria, anemia is defined as blood hemoglobin (Hb) con- the patient has over his/her own life, full of patterns that centration < 130 g/L (< 13 g/dL) or hematocrit (Hct) < are so particular to him that is for nobody to judge nor- 39% in adult males; Hb < 120 g/L (< 12 g/dL) or Hct < mal. It is hard (if not impossible) to make these diagnos- 37% in adult females. The signs and symptoms depend tics with no judgment values. on the level and on the time course. In the same vein, Fried and Agassi’s work on paranoia The demarcation here is objective and quantitative, for example demarcate normal from the pathological in the parameter varies only according to the sex. The BST terms of a deficiency in cognitive self-correction, since seems a proper model to apply. The end point function the psychotic individual does not acknowledge a distinc- is carrying oxygen throughout the body, this being es- tion between his distorted view and reality [5, 9].. sential to survival. Anemia is a priority worldwide, pol- icies made, resources allocated, industries revolve over Psychopathy this subject and disinformation abounds. Moreover, by Psychopathy, as in antisocial behavior and impaired em- its 32.9% prevalence in general population, society as a pathy, remorse and egotistical traits can be nothing less whole is diseased to a great extent [1, 14].. than appropriate in a context where unfairness rules, This definition of anemia is only quantitative and does where inequality is evident, and where suffering, if not not incorporate signs and symptoms which poses prob- seen before our eyes, is of well-known existence some- lems to the clinical value of the diagnosis. People with where around the globe. hemoglobin values outside this range can live without Wakefield sets his goal as distinguishing normal suffer- any other signs or symptoms, which exposes the prob- ing from , so that there is a solid founda- lem of defining a diagnosis according to BST framework. tion for critique of overly expansive psychiatric diagnosis The reasoning that explains how values outside this that pathologizes normal variation [15]. Normality can range determine loss of function, and how this lack of be arguably seen as a process where there is adaptation function (either in relation to reproduction or survival as to a certain context, with self-organization in terms of the BST states) can be measured, seems to be the un- values, which can represent Biological Advantage, in the answered core question in this type of framework. sense that it can be seen as a coping mechanism with Interestingly, the Process framework would allow an harsh realities. approach that highlights changes during time in the same individual according to his/her clinical condition. Discussion More than the absolute value, the focus is on the inter- To meet the challenge of conceptualizing normality in pretation of its variations. medicine in such a way that it can be seen as a simple and practical tool, some of the points formerly discussed Psychiatric diseases must be retained and others added. The Diagnostic and Statistical Manual of Mental Disor- To begin with, in the humble view of this analysis, ders (DSM), is the American reference book for the normality in medicine cannot be a synonym with health. Catita et al. Philosophy, Ethics, and Humanities in Medicine (2020) 15:3 Page 5 of 6

The arguments studied were not sufficiently strong to be a matter decided by experts, is now being replaced by a worth the costs of such an assertion. The impact is so perspective that privileges the human being as the sub- broad, it is both political and individual, and telling that ject empowered to rule the decisions with impact in his/ the normality is health can only be appreciated as an her health, in a smaller or larger scale. Accordingly, Hu- ideal. Even when using statistical norm and subnormal man Rights are treasured and above all views on society values to evaluate the health of someone, using a natur- conceptions, the individual being the center of every- alist approach, non-value laden, even if according to pa- thing, from social decisions to medical actions. An ex- rameters used generally in biology, as in the most ample of this is the European Council Recommendation prevailing theory the BST, normality as health still im- four on principles concerning the legal protection of in- plies a reduction in meaning. Even though the health capable adults, where it is stated that “there is a recogni- care practitioner can normalize parameters, and to do so tion that existing freedoms and capacities should be uses evidence-based medicine that applies and preserved as much as possible and those measures which ranges to the advantage of the patient morbidity and needlessly take away people’s rights are indefensible”. mortality rate, this is not enough to determine the best A model to normality must address diversity. And for interest of a given individual. Being normal is more than this, the aspect of process is of great advantage. It is use- experiencing health since it entails managing both ful to consider that for normality to be achieved, what a healthy and non-healthy states. Likewise, unhealthy person wants to achieve is important. Autonomy should people could be considered normal when able to cope be considered, and albeit possibly unhealthy, it is not ab- with disease. Self-limited events such as flu, gastroenter- normal. Individuals are entitled to transform themselves, itis, anxiety or minor chronical conditions such as both by changing their physical aspect and by practicing gastro-esophageal reflux disorder are frequent and can their values and preferences. The implications of using be understood in the light of this conception of or refusing medical tools to enhance self-determination normality. and what constitutes this must be socially discussed and This conception of normality suits the Biopsychosocial legal frameworks created. An array of divisive topics model contemplated by Engel as another element that could be named, such as abortion, euthanasia, trans- articulates with its concepts of health, wellbeing, social gender hormone therapy or drug abuse. However, while well-being as well as disease, illness and sickness. Ac- public opinion may judge with both legal and moral ar- cording to the Biopsychosocial model, health has a bio- guments, science must preserve its systematic and lo- logical, psychological and social dimension that when gical approach, observing and analyzing facts. In this disrupted causes an illness (psychological dimension), way it favors the impartiality of the conception of what which is the human experience of the disease (biological is normality in medicine and elevates discussions of dimension) and that defines the subject as sick (social di- other disciplines that are entitled to create boundaries. mension )[4]. In the same line, normality as it is concep- In a similar fashion of what could happen with normality tualized in here also takes into account this subjective in medicine, the entitlement to self-determination experience of disease, the social context of the individual already protects individuals from public scrutiny in other and its biological aspects, integrating them in order to domains as for example religious matters. better understand the problem and to design an health- care action plan. Denoting normality as a concept differ- Conclusion entiated from health and disease, people are thus The subject of normality in medicine underlies clinical empowered to manage their health condition. practice and has several implications in public life, hav- No longer should the individual consider himself/her- ing been discussed since ancient times in those contexts. self abnormal for having any health condition, but rather Assuming the need for a clear concept and pursuing it the emphasis of this concept of normality is for him/her is urgent and in this text the most accepted definitions to evaluate his/her normality in the attitude to manage in the academic community were analyzed and grouped it. This management can be made according to Ideal into models. Then three case studies were chosen: goals that work as reference points to the design of an anemia, psychiatric diseases and psychopathy, and com- action plan focused on the Process, which takes biostat- mented in the light of these models. istical information into account, and determines what is Normality has been often synonym with health, either Health conforming to personal specificities, considering by the BST or other theories, and this is the most popu- which can constitute Biological Advantages. lar definition. Nevertheless, it has been employed mean- The current perspective over health and normality fo- ing an ideal, a process or a biological advantage. cuses autonomy, and autonomy surpasses other ethical The conception of what is normal is not debated fre- values. In situations of less autonomy that before were quently and due to its philosophical character is hard to regarded with a paternalistic look, where normality was set clear questions and answers. Catita et al. Philosophy, Ethics, and Humanities in Medicine (2020) 15:3 Page 6 of 6

From this analysis the authors realize that the most 8. Nordenfelt L. Concepts of health and their consequences for health care. common model that equates normality with health, al- Theor Med. 1993;14(4):277–85. 9. Rudnick A. The ends of medical intervention and the demarcation of the though being intuitive is very infrequent, since there are Normal from the pathological. J Med Philos. 2000;25(5):569–80. https://doi. very little individuals that are healthy strictly speaking org/10.1076/0360-5310(200010)25:5;1-W;FT569. and there are large communities of people highly 10. Schmidt JM. The concept of health - in the history of medicine and in the writings of Hahnemann. Homeopathy. 2010;99(3):215–20. https://doi.org/10. adapted to living with diseases. Accordingly, these indi- 1016/j.homp.2010.05.004. viduals would also be unfit for the other models of nor- 11. Schwartz PH. Reframing the disease debate and defending the biostatistical mality considered. theory. J Med Philos. 2014;39(6):572–89. https://doi.org/10.1093/jmp/jhu039. 12. Stempsey WE. Emerging medical technologies and emerging conceptions Therefore, the authors realize that these models re- of health. Theor Med Bioeth. 2006;27(3):227–43. https://doi.org/10.1007/ quire a redesign, and stress the importance of integrating s11017-006-9003-z. aspects like variability and the respect for autonomy. 13. Täljedal I-B. Strong holism, weak holism, and health. Med Health Care Philos. 2004;7(2):143–8 discussion 149-152. With the development in societies and advances in 14. Tauber AI. Darwinian aftershocks: repercussions in late twentieth century medical information and technologies a clear definition medicine. J R Soc Med. 1994;87(1):27–31. of its purposes demands further thinking about what is 15. Wakefield JC. The biostatistical theory versus the harmful dysfunction analysis, part 1: is part-dysfunction a sufficient condition for medical normality in medicine. disorder? J Med Philos. 2014;39(6):648–82. https://doi.org/10.1093/jmp/ jhu038. Acknowledgements Not applicable. Publisher’sNote Authors’ contributions Springer Nature remains neutral with regard to jurisdictional claims in MT and PM designed the study; MT performed the bibliographic search; MT, published maps and institutional affiliations. AA and PM wrote the manuscript; All the authors approved the final version.

Funding Not applicable.

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Competing interests The authors declare that they have no competing interests.

Author details 1Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal. 2ICBAS – Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal. 3ICVS-3Bs PT Government Associate Laboratory, Braga/ Guimarães, Portugal.

Received: 12 December 2019 Accepted: 25 March 2020

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