How Sick Are Patients in Clinical Trials? What Does That Mean for the Clinician?

In recent years, an increasing number of industry-sponsored clinical trials of antidepressants have found the active medication to be no better than placebo. Because the placebo response is lower in severe depression, these failed studies have been thought to reflect recruitment of less severely depressed patients, who have high rates of response to placebo and of spontaneous improvement. In this study, which had no support from drug companies, researchers aimed to determine how requiring more severe depression for study inclusion would affect differences in outcomes with an investigational antidepressant and placebo.

The researchers reviewed data from 51 clinical trials performed for FDA approval of 10 antidepressants in 11,270 patients. On…