Clinical Global Impression
Also written as: CGI — Clinical Global Impression Scale
Standardized assessment tool used to measure illness severity, treatment response, and efficacy in psychiatric research and practice.
Full Definition
The Clinical Global Impression Scale (CGI) is a widely used clinician-rated instrument that provides a global assessment of psychiatric symptom severity and treatment response. The scale consists of three components: CGI-Severity (CGI-S) rates current illness severity from 1 (normal) to 7 (extremely ill), CGI-Improvement (CGI-I) measures change from baseline from 1 (very much improved) to 7 (very much worse), and CGI-Efficacy Index considers both therapeutic effect and side effects. The CGI is valued for its simplicity and clinical relevance, making it useful for treatment monitoring, clinical trials, and quality improvement initiatives in psychiatric settings.
Usage
Usage note: Specify which CGI component (S, I, or EI) when documenting scores
In Context
- "The patient's Clinical Global Impression-Severity score improved from 6 (severely ill) to 3 (mildly ill) after medication optimization." — Treatment progress note
- "CGI-Improvement ratings will be collected monthly to track treatment response in the clinical trial." — Research protocol documentation