Disability models in geriatrics: comprehensive rather than competing models should be promoted

The usefulness of different models of disability is discussed. There is no clear-cut demarcation between ability and disability, and a person's functional abilities are highly dependent on societal as well as individual factors. One should not, however, promote models of disability that cover only the social aspects, but rather try to build comprehensive models including medical, psychological and social aspects of disability. The World Health Organization's International Classification of Impairments, Disabilities and Handicaps (ICIDH) provides a useful basis for such model building. The main weakness of the ICIDH is that it fails to take the subjective perceptions of the individual fully into account. Accordingly, it should be supplemented by some model of subjective well-being. Possible relationships between subjective well-being and the ICIDH concepts are discussed.