Health includes all kinds of aspects that can vary in time and place. Health has appreciative, standardization, and cultural aspects. In everyday parlance, for example, the concept of health in an appreciative or even standardized sense is applied. Healthy is seen as a synonym for “good,” as in “use your common sense.” It sometimes seems to replace health standards and precepts: you must do something or not (for your health). Also, culture affects the way in which health is experienced. Within the various cultures there are different accents on the sense of health. It is true that—apart from these cultural accents—health is generally considered important.

Medical, monocausal vision of health. Dealing with health and disease has long been exclusively a matter for doctors. Medics dealt with sick people and they sought to heal the sick. From the classic, medical approach to health, health is regarded as the absence of disease and body defects. According to this medical approach, everyone is healthy who is not sick. This is a monocausal explanation of health and disease. In this view of the genesis of disease, disease has only one cause. This view has existed since the discovery of micro-organisms as the cause of illness. When the cause is identified, then a person is sick. If such a cause is not identifiable, there is health. This is also known as the professional, medical approach to health.

For a long time, for nursing professionals too, this was the main view of health, but not any longer. For many health problems that we face in our time (such as cancer and damage to the blood vessels), this monocausal approach shows deficits. There are a number of reasons why the professional, medical approach is an incomplete representation of the present reality of health and disease. One reason is that more than one factor may affect the development of a health problem; thus, the health problem is not monocausal but multifactorial. A second reason is that current health problems develop insidiously, unseen, so that a clear transition from health to disease is not possible.

According to the biological vision of health, there is constant adjustment of physiological processes and biochemical reactions in the body to external circumstances. These internal processes and biochemical reactions are kept constant by the body. Survival of the individual is determined by the extent to which the organism is capable of keeping his internal environment (for example, body temperature, acidity of the blood) within narrow limits and to keep it constant at ever-changing external conditions. We call this homeostasis. According to this biological, organic approach to health, a person is healthy if he is able to keep his internal environment constant under varying external conditions. Biological health can be accurately defined and is universally valid for every human being. Nursing professionals can determine the biological health of patients by certain acts, such as the measurement of the body temperature and blood glucose levels.

According to the psychological vision of health, health is defined as the capability of a person to achieve self-imposed goals in life. For the psychological view of health, it is important to feel mentally healthy and capable of meeting your own spiritual needs. A person is healthy when he feels mentally and spiritually optimal. A person is sick when he is not able to satisfy his mental and spiritual needs, because he cannot handle these needs. People who have a blemish or are sick, may feel and define themselves as healthy, according to this approach. The psychological approach emphasizes the mental and spiritual dimensions. The approach is very personal and is therefore called the individual approach to health. Nursing professionals can gain insight in the psychological health of the patient by observing and talking with patients.

According to the social vision of health, a person is healthy if he can perform his social roles in the society. A person is healthy if he upholds, within the social roles assigned to him, the values and standards in force in society. In this approach to health, social adjustment is central and the individual with his own needs and desires is subordinate. A person is sick if he is unable to adapt to and behave in accordance with the prevailing values and standards of its culture. Nursing professionals can highlight the social aspects of patients’ health by paying attention to social functioning. For example, nursing professionals can ask whether the patient manages to take care of her children, or if she manages to go with a parent or child to the specialist, or if she is capable of combining a (busy) work situation with bringing up teenage children.

In addition to the medical view, with its monocausal approach to health, there is increasingly room for a multicausal, multifactorial view of health. This links the biological, psychological, and social visions of health. In 1948, the World Health Organization defined health as: http://​www.​who.​int/​about/​definition/​en/​print.​html “A state of complete physical, mental and social well-being and not merely the absence of disease or physical defect.” We call this the humane approach to health.

In this view of health, people are more than just a body, there is a much wider and more positive approach to health compared with the classic, medical approach. There is—apart from attention to purely physical factors—attention to psychological and social aspects of health. These dimensions on health reflect a holistic view of human beings. The humane approach to health is committed against the limitations of the classical, medical approach. But, the term “well-being” is difficult to interpret in this definition. Well-being as a concept is hard to define, and involves a value judgment. The interpretation of well-being is individually determined and depends on an individual’s own values and standards. The WHO reformulated the definition of health (but the above definition is still the one that is mostly used), namely: “A dynamic state of complete physical, mental, spiritual and social well-being and not merely the absence of disease or infirmity.” (WHO 1998) (http://​www.​who.​int/​bulletin/​bulletin_​board/​83/​ustun11051/​en/​)

The question is whether the WHO’s view of health is useful for nursing professionals. The humane vision offers nursing professionals no clear criterion under which they can classify people as sick or healthy. The main reason for this is that complete physical, mental, and social well-being is impossible. This approach to health offers an insufficient basis for “distinguishing” between healthy and unhealthy people. However, the definition does give an insight into the quest and the targeting of health, and is therefore of great importance for the nursing profession. The WHO definition offers nursing professionals clear points of reference and the holistic view of human beings is now commonly the starting point within the nursing profession for good quality and responsible care (Fig. 1.1).

A final vision of health is the dynamic view, taking into account the aspect of changing health. This approach to health focuses on the adaptability of people and achieving a balance between man and his (external) environment. For health, beneficial influences of interest and threats play a role. People’s health is threatened or promoted to a greater or lesser extent. This negative or positive influence may change or disappear. Positive influences are a condition for health, whereas negative influences have no use or a harmful effect on health.

Health is the ability of humans to adapt to psychological, social, and physical factors that influence a person. This adaptability to be the director in his own life and that he manages his own health. The health problem is not central, but instead human adaptability to changing factors and influences. The person would always have to adapt to changes, whether temporary or not, for psychological, social, and physical conditions. Further, the balance between load capacity and carrying capacity is important for health. The concept of “disease” will then be given the general sense of being “out of balance.” The concept of “health” will then be given the general sense of being “in balance.” According to the dynamic vision, a person is a holistic unit and healthy as he is in balance with both himself and his external environment.

For nursing professionals, from the dynamic viewpoint of health, adaptability and self-management are important. Patients experience (both objectively and subjectively) a certain balance in load capacity and wear force between themselves as a holistic unit and positive and negative influences from the environment. A definition of health that is appropriate to the dynamic vision of health: health is not simply the absence of disease, it is something positive, a joyful attitude toward life, and a cheerful acceptance of the responsibilities that life puts upon the individual (Breslow 1999).

The International Classification of Functioning, Disability, and Health (ICF) is the WHO framework for measuring health and health problems, both at an individual and at a population level. What is innovative about this framework is that disorders, limitations, and participation problems are part of the measurements of a health problem. The “count” of disorders, limitations, and participation problems in identifying health problems is the goal of the ICF. The ICF is used as a planning tool for decision-making in health care. For example, if the number of patients with chronic health problems increases, then adjustments are necessary in the care and in the planning of medical care facilities. The goal is also to measure health outcomes and reporting and to analyze health interventions for statistical purposes. The WHO has developed a checklist to measure the functioning of the patient at an individual level. This checklist includes not only medical data, but also the social data of the patient, health status, activities, and participation (Fig. 1.2).

Using the ICF, we start from the health problem, and look at the disorders, constraints, and participation problems resulting from the health problem. The disorders may be related to bodily functions and anatomical features. The limitations may be related to the activities that the patient can perform. The participation problems include the extent to which the patient may participate. By interacting with the patient with a health problem, a nursing professional can focus on maintaining health or promoting health. Based on the ICF, the starting point of nursing care is the adaptability of the patient; thus, his ability to be the director of his own health and to optimize his self-management (within the given frameworks of possible disturbances, limitations or participation problems).

Health is a broad concept and may be seen from different viewpoints. But these views are not useful for the description of the health of an individual or a population. To describe the health of an individual or group, we use the term health status. The health status can be described using health indicators. Health indicators are the objective and measurable quantities of health and disease.