Physical therapy diagnosis and the relationship between impairments and function.

Physical therapy diagnosis refers to both a process and a particular label within a classification scheme. This article reviews the development of the concept of diagnosis in physical therapy and evaluates the clinical utility of using the World Health Organization's International Classification of Impairments, Disabilities, and Handicaps (ICIDH) as a taxonomy for physical therapy. In place of the ICIDH, a model developed by Nagi is suggested. If this model is applied to physical therapy, the relationship between impairments and functional limitations is identified as the primary diagnostic focus of physical therapy. Exploration and expansion of this model may best serve the development of a classification scheme for physical therapy diagnosis.