A placebo-controlled study of sertraline in the treatment of outpatients with seasonal affective disorder.

Rationale: Seasonal affective disorder (SAD) is a relatively common cyclical depressive illness characterized by seasonal depressions during winter. The disorder is commonly responsive to light therapy, but antidepressant drug efficacy has not been definitely established. Serotonin selective re-uptake inhibitors are potentially efficacious treatments for SAD.