An assessment of the understanding and motivations of patients with schizophrenia about participating in a clinical trial.

Enrollment of an adequate number of subjects for a clinical trial is a perennial challenge and this might arguably be even more difficult and complex in trials involving patients with schizophrenia. In this paper, we used a modification of the Prospective Preference Approach (PPA) as a prelude to an actual randomized placebo-controlled trial of a cognitive-enhancing agent for patients with schizophrenia. This approach sought to test and enhance subjects' understanding of the key concepts of the trial, and administered the PPA at baseline and following a brief educational module.