Which depressions respond to placebo?

This descriptive study of 55 outpatients with unipolar major depression compared placebo responders (n = 21) and placebo nonresponders (n = 34) with respect to demographic, diagnostic, history of illness and symptomatic features of the current episode of depression. Placebo responders were significantly more likely to be nonendogenous and were more likely to meet criteria for another Research Diagnostic Criteria diagnosis. Additionally, placebo responders were characterized by a shorter length of illness and reported a lower level of depressive symptomatology on the Beck Depression Inventory and the Carroll Rating Scale. Clinician-rated depressive symptom severity (e.g., Hamilton Rating Scale for Depression, Covi Global Anxiety Scale, and Raskin Depression Rating Scale) and demographic variables did not differentiate placebo responders from nonresponders. These data suggest candidates for antidepressant treatment and implications for antidepressant drug trials.