What is health and what is positive? The ICF solution
Authors: MICHAEL LINDEN
Journal: World Psychiatry (2012)

When talking about positive health, a clarification of concepts and definitions is essential. Vaillant gives a spectrum of answers, but raises at the same time even more questions which need a detailed discussion. A first question in need of clarification is what is meant with “health”. Additional to what is discussed by Vaillant, a definition is needed of what is meant with “positive”, and whether “positive” and “health” are synonyms. Vaillant points to exceptional persons like astronauts or decathlon champions. This suggests that positive health is something different from health as such, i.e. health of ordinary persons. If this is meant, the question is, who is interested in extremes of health, and can these be called health at all? Is the disfigured heart of an athlete healthy or is it sick, as it may kill the person in spite of the fact that it temporarily helps to achieve high scores in sport? And is persistent happiness and well-being not called hyperthymia? So, what is the criterion to say that something is “healthy”? We need norms and Vaillant is correct in saying that they can neither be taken from distributions of scores nor from achievement. A second question in need of clarification is the relation between health and illness. Vaillant says that “mental illness is a condition that can be defined reliably” and he then contrasts mental illness with “positive mental health”. Contrary to the traditional view that “health” and “illness” are two ends of a one-dimensional continuum, Vaillant proposes a two-dimensional concept, e.g., when talking about a world class soccer player with a broken ankle who is ill and healthy at the same time. The assumption that health and illness are two independent dimensions allows to study the interaction between them, and not only to measure but also to address both illness and health specifically. Especially in the treatment of chronic illness, like myocardial infarction, cancer, or anxiety, the problem is in many cases not so much the illness but the deterioration of health because of the illness. We have called this the “cuckoo's-egg-syndrome”. In order to have a beautiful garden, it is not enough to tear out weeds (addressing illness), but you also have to plant flowers (improving health). There is a long list of well-evaluated interventions for the improvement of health, which we have summarized under the term “salutotherapy” 1. A third question in need of clarification is what dimensions are included under the term “health”. Vaillant points to seven areas of psychological research, but there are further concepts of interest like personality, cognitive intelligence (not only emotional intelligence), activities of daily living, workability, coping, social competence, self efficacy, adaptation, purpose of life psychology, wisdom psychology, quality of life, sense of coherence 2,3,4,5. These are also important dimensions in describing the psychology of health and each is supported by a large body of research. One more question is why only psychological constructs are discussed. Are there no biological or somatic dimensions of mental health? 6. In summary, the conclusion is that the problems with health are the same as with illness. There is no general definition of illness nor of health which catches all aspects. There are many illnesses, with quite different definitions and criteria, and similarly we should talk about many different forms of health. The structure of Vaillant's paper goes in this direction, as it discusses not health but resilience, well-being, etc., which are all important, needed, and helpful dimensions, but which are not “health as such”. Is there a way to answer the open questions and come to a “differential diagnosis” of health? The International Classification of Functioning, Disability, and Health (ICF), produced by the World Health Organization 7, can serve as a frame of reference for the classification of health, as the ICD in the classification of illness. The ICF describes “functional health” by discriminating between function, capacity, environment, person, and participation. Capacity is qualified in reference to context factors, which solves the problem of norms 8. This is analogous to intelligence tests, where the intelligence quotient is calculated also on the basis of, for example, age and education. The ICF covers somatic and psychological functions, and includes a list of activities and context factors as well as recommendations for their assessment. The ICF provides a frame in which one can include all the different concepts discussed by Vaillant, showing that we do not have to look for “the” definition of health, since there are many “healths”, which become of interest to therapists whenever they are needed, endangered, or impaired in a given individual and at a given time 8,9,10.