Depression Level and Suitability of Drug Treatment

Previous studies have suggested that antidepressant efficacy is greater in patients with more-severe depression, but these analyses may have minimized effects by using designs that restricted the patient population (via initial placebo washouts and high baseline depression-severity scores for inclusion). In this meta-analysis, researchers carefully selected six placebo-controlled studies in which imipramine or paroxetine treatment lasted at least 6 weeks, placebo washout was not used, individual-level data were available, and patients (N=718) had a broad range of baseline depression severity.

Drug–placebo differences in symptom change varied substantially with baseline depression level (Hamilton Rating Scale for Depression [HRSD], ≤18: drug …