GAD-7

The Generalized Anxiety Disorder 7-item (GAD-7) scale is a brief self-report questionnaire developed by Robert Spitzer and colleagues in 2006 to screen for and measure the severity of generalized anxiety disorder. Each of the 7 items asks how often the respondent has been bothered by a specific anxiety symptom over the past two weeks, rated 0–3 (not at all to nearly every day). Total scores range from 0 to 21. While developed for GAD, the scale also performs well as a screener for panic disorder, social anxiety disorder, and PTSD. The GAD-7 is widely used as a secondary endpoint in psychedelic clinical trials due to its brevity, free public-domain availability, and strong psychometric properties (sensitivity 89%, specificity 82% at cutoff ≥10). It is often paired with the PHQ-9 for combined depression and anxiety assessment.