Clinical Global Impression Scale
A measure of psychosis which rates the severity of psychotic symptoms on a scale from 0–no symptoms, to 7–major issues.
The CGI was developed for use in NIMH-sponsored clinical trials to provide a brief, stand-alone assessment of the clinician’s view of a patient’s global functioning before and after initiating a study medication. It provides a clinician-determined summary measure that weighs all available information, including a knowledge of the patient’s history, psychosocial circumstances, symptoms, behaviour, and the impact of the symptoms on the patient’s ability to function.
The CGI Scale is comprised of two one-item measures evaluating:
(1) Severity of psychopathology on a scale of 1 to 7 and
(2) Change from the onset of treatment on a scale of 1 to 7.
Synonym CGI Scale
References Psychiatry (Edgmont). 2007 July; 4(7): 28–37
Guy W, ref 47, NEJM 1999; 340:757