Attitudes of patients with schizophrenia toward placebo-controlled clinical trials.

Background: Despite the fact that the efficacy of antipsychotic treatment in patients with schizophrenia has been demonstrated in numerous double-blind studies, placebo-controlled studies are still commonly performed. Although much is known about the opinions of professionals concerning this issue, so far nothing is known about the opinions of patients who are most affected by the realization of placebo-controlled clinical trials.

Method: In a cross-sectional study from June 2000 to January 2001, 100 inpatients and outpatients with ICD-10 schizophrenia or schizophreniform disorder were investigated by using a questionnaire specifically developed to survey patients' attitudes concerning possible participation in placebo-controlled clinical trials. Psychopathology and side effects were physician-rated.

Results: 56% of patients would not be willing to participate in a placebo-controlled clinical trial. On the other hand, only about 16% of the patients are against clinical trials in principle. Gender, treatment, severity of psychopathology (Positive and Negative Syndrome Scale), adverse events (UKU Side Effect Rating Scale), and attitude toward medication (Drug Attitude Inventory) had no statistically significant influence on the decision. Most of the patients (76%) stated that they would not lose trust in their physician if asked to participate in a placebo-controlled clinical trial.

Conclusion: The opinions and fears of patients who are most affected by the debate need to be considered when deciding whether a placebo-controlled clinical trial is necessary.