Disease, illness and health: theoretical models of the disablement process.

Handicap is the result of a process of disablement whose origin is a pathological condition (disease). According to some definitions of health (e.g., a state of complete physical, mental and social well-being), the classical biomedical concept is too restrictive to cover all the consequences of disease. New models have been proposed: the impairment-disability-handicap model presented by WHO, the situational handicap model, and the quality-of-life model. A unifying schema of the disablement process includes these concepts and provides a useful way of analysing the consequences of disease. Factors that modify the disablement process can be identified by their respective impacts, and provide operational guidelines for public health interventions.