Disablement outcomes in geriatric rehabilitation.

Until recently, knowledge in the field of geriatric rehabilitation has been based largely on empirical findings. There is a need for greater conceptual clarity about major disablement outcomes to provide a foundation for future theoretical research. Disablement terms promulgated by the World Health Organization's (WHO) International Classification of Impairments Disabilities and Handicaps (ICIDH) are reviewed and compared with those of an alternative model proposed by Saad Nagi in 1965. Distinctions are drawn between the disablement concepts each system includes to refer to (1) inherent attributes of patients and (2) the interaction of the patient with the social and physical environment. The importance of a disablement model reflecting this distinction between inherent and relational concepts is emphasized. Areas for fertile research opportunities in which the disablement concepts could be used are discussed. It is suggested that improved understanding of disablement outcomes could be most readily achieved by application of an epidemiologic model separating the factors affecting outcomes into three sets of variables: the host factors representing intra-individual attributes; the agent factors, which are the external event or events causing the disability; and the environmental factors, which relate to the physical or social surroundings in which the disability occurs. In future research efforts, a more theoretical approach to studying disablement outcomes is advocated as a basis for improvements in geriatric rehabilitation.