Toward a common language of disablement.

FUNDAMENTAL to advancing the science of disablement is the ability to communicate with one another and to speak in a common language that is understood across related professional fields and disciplines. Within the United States, Nagi's Disablement Model has proven useful as a language used by researchers to delineate the consequences of disease and injury, both at the level of body systems, the person, and society (1–4). For Nagi, impairment refers to a loss or abnormality at the tissue, organ, and body system level. At the level of the individual, Nagi uses the term functional limitations that represent restrictions in the performance of specific tasks by a person. The term disability, as defined by Nagi, refers to the limitation in performing socially defined roles and tasks expected of an individual within a sociocultural and physical environment. These roles and tasks are organized in spheres of life activities such as those of the family or other interpersonal relations; work, employment, and other economic pursuits and education, recreation, and self-care.