Objective: This study sought to determine the extent to which key aspects of a clinical trial's protocol were recalled by participants entering a clinical trial for alcohol and illicit substance-use treatment after standard informed-consent procedures, as well as to explore the possible relationships between recall, neuropsychological functioning, and substance-use outcomes.
Method: Before entering a randomized clinical trial testing the effectiveness of a computer-based training version of cognitive-behavioral therapy, 76 participants (55% male) meeting criteria for current substance dependence (according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) completed a 14-item true/false quiz that assessed their comprehension of basic information provided in the consent form.
Results: Only 15% of participants correctly answered all 14 consent quiz items. The percentage of correct recall was associated with measures of intelligence (r= .29, p = .01) and attention (r = -.26, p = .04). Quiz scores were also moderately associated with the amount of substance use during the treatment period (r = -.26, p = .03).
Conclusions: These findings highlight the importance of formally evaluating research participants' understanding of the informed-consent process, and they call to attention the potential utility of a brief neuropsychological screening to identify individuals in need of enhanced consent procedures, particularly within vulnerable populations, such as substance users.