OBJECTIVE: Clinical management of aggression depends on the availability of easily administrable measurements allowing reliable evaluation. The present study's aim is to validate a Clinical Global Impression-Severity of Aggression scale (CGI-A). METHOD: 558 inpatients with psychiatric disorders and an agitated-aggressive syndrome at baseline were continuously assessed over 5 days using CGI-A and the Positive and Negative Syndrome Scale-Excited Component (PANSS-EC). Equipercentile linking, correlation analyses and linear regression were applied. RESULTS: Relationship between CGI-A and PANSS-EC total score was found to be linear. On a 5-level CGI-A scale, values of 1 to 5 points were found to correspond to PANSS-EC scores of 12.2, 16.7, 21.3, 25.8, and 30.4, respectively (average increase: 4.6). All findings remained stable when only data from patients with schizophrenia spectrum disorders were analyzed. CONCLUSIONS: The CGI-A is proposed as a quickly administrable scale for the assessment of patients' aggressiveness.
