Placebo response rates in psychotic and nonpsychotic depression

The authors reanalyzed data from two earlier studies that used double-blind placebo-controlled formats to study the efficacy of amitriptyline. Using a 14-day drug-free 'wash-out' period, they found that the placebo response rates were 0% for psychotic depressives and 13.3% for nonpsychotic depressives. Amitriptyline was significantly superior to placebo for both psychotic (P less than or equal to 0.05) and nonpsychotic (P less than or equal to 0.05) depressed patients.