The measurement of disability.

The frequent occurrence of desynchrony between psychiatric symptoms and disability makes it necessary to measure disability/ functional impairment in addition to psychiatric symptoms when tracking treatment outcome. Existing disability measures in psychiatry are comprehensive but lengthy. There is a need for short, simple, cost-effective, sensitive measures of disability and functional impairment in psychiatric disorders. We developed a discretized analog disability scale (DISS) which uses visual-spatial, numeric and verbal descriptive anchors to assess disability across three domains: work, social life and family life. The DISS has proved to be very sensitive to change in drug treatment studies in psychiatry. The usefulness of the DISS in assessing disability in terms of work, social and family relationships is discussed.