Factors associated with refusal to enter a clinical trial: Epidural anesthesia is a deterrent to participation

Abstract

Purpose: To compare patients who participate in a clinical trial for pain management involving epidural anesthesia to those who refuse and document their reasons for refusing. Methods: Demographic and health history information was collected from 621 female patients who were screened for inclusion in a pain management trial involving epidural anesthesia. Patients who completed the clinical trial (n = 149) were compared to those who consented to provide screening information but did not enter the trial (n = 472). Results: Sixty-seven percent of women who refused cited unwillingness to have an epidural as the reason for their decision. Non-Caucasians (P < 0.01), patients with no history of mood/anxiety disorders (P < 0.016) or systemic disease (P < 0,02), and patients with certain types of pain (P < 0.02) were more likely to refuse to participate in the clinical trial. A longer duration between recruitment and surgery was also found to be associated with higher participation rates (P < 0.01). A logistic regression equation significantly predicted which patients would participate or refuse (P < 0,0001), indicating that a specific set of health and demographic factors strongly influence the decision to participate in a trial. Conclusions: The decision to participate in a clinical trial is viewed as a risk/benefit analysis. Factors such as short recruitment to surgery intervals and pre-existing pain, which increase the salience of risks associated with the trial, may result in lower participation rates. Overall, epidural anesthesia is a strong deterrent to participation in a clinical trial.