The Global Assessment of Functioning (GAF) Scale is a numeric scale used by mental health clinicians and physicians to rate the social, occupational, and psychological functioning of an individual. Scores range from 100 (extremely high functioning) to 1 (severely impaired).
The scale was included in Diagnostic and Statistical Manual, Fourth Edition, Text Revision (DSM-IV-TR), but replaced in The Diagnostic and Statistical Manual of Mental Health Disorders, Fifth Edition (DSM-V) with the World Health Organization Disability Assessment Schedule (WHODAS), an interview with detailed items. The WHODAS is supposed to be more detailed and objective than a single global impression.
To see the GAF Scale, click here.