Health is a condition of mental, physical and emotional well-being where infirmity and disease are absent. It has been described as a progressive condition affecting the whole human body and mind, resulting in the prevention of disease and impairment of functioning of the body and mind. It is the result of a combination of genetic and environmental factors, the effects of which are cumulative over time. This definition is very broad and it is important that one considers all the possible consequences and take into account the various factors affecting health.

The definition of health care will differ according to the service provider. In most instances, the definition of health care providers will be influenced by hospital practices and other aspects of a community or insurance organization. These organizations define health care on the basis of cost management principles. As health care costs continue to rise, many health professionals are advocating for an improved definition of health care that is more in line with the primary definition of health which is a subjective state of the body and not a physical state. There is some resistance to this concept; however, the focus on health as a subjective state has been adopted by many health professionals such as physicians.

On another level, mental health is more closely associated with wellness. It is the combined effect of physical illness and poor health that causes degradation in one’s quality of life. Mental health is related to the well-being of the person and therefore is related to his capacity for self-care and for maintaining positive relationships with others. It is measured using several specific domains that include emotional well-being, physical health, competence, vitality, and involvement or community involvement. This domain of mental health was first measured using the Well-Being Questionnaire (WQ-1) in the 1970s.

The most common dimensions used to define health are the physiological (blood pressure, cholesterol level, blood sugar level, and respiration) and the mental dimension (cognition, thinking, and memory). However, these dimensions only provide a starting point for measurement. The need for a comprehensive dimensional definition of “health” emerged because different domains of health were being measured separately and in many cases were then confounded by the existence of unhealthful behaviors. The resulting theory of a comprehensive concept of healthful lifestyle was first put forth by investigators based in the National Institute of Mental Health (NIMH).

In general, this theory of a health system requires at least one domain of concern that is shared by the major domains of health care. It should also be possible for a single indicator to control multiple outcome measures. For example, a single measure of smoking prevalence can effectively control outcomes for both quitters and non-quitters. Similarly, a single dimension can specify the type of treatment received by smokers and non-smokers. More recently, researchers have developed the concept of health systems in which a set of common metrics are used to specify the health system and to monitor its progress towards its goal.

The most common health systems concept is operationalized as follows. A health system is defined by a set of primary outcomes that are measured over time and which are used to characterize the system. The primary outcomes are then linked to one or more secondary outcomes that reflect the effect of the changes in the primary outcomes on the secondary outcomes. The concepts of health systems are typically operationalized in a way that they are operationalized in terms of one group (for example, community) or on the basis of population. The concept of health systems is therefore not just a description of a process that describes a system, but also describes how an operationalized definition of a health system can be used to link health system interventions with particular individuals and populations and how these associations affect the quality of that intervention. For example, if an intervention affects one group of people in a community, the community health system is said to have a health system definition that is local to that group.