Hamilton Depression Rating Scale

The Hamilton Depression Rating Scale, published by Max Hamilton in 1960, is a clinician-administered interview assessment of depressive symptom severity. The most common version contains 17 items (HAM-D-17), though 21-item and 24-item versions exist. It is considered the gold standard outcome measure in antidepressant drug trials and remains the most cited depression rating scale in the psychiatric literature. Unlike self-report measures, HAM-D requires clinician judgment and observation, making it particularly valuable in research settings where standardized measurement by trained raters is essential.