Objective: Relatively little attention has focused on the impact of psychiatric conditions on human subjects' comprehension of consent information. The purpose of this randomized study was to determine whether depression affects comprehension and recall of informed consent information among persons with Parkinson's disease and their caregivers and to evaluate the effects of support on comprehension and recall during the consent process.
Method: Comprehension and recall of information were assessed using a modified version of the Modified Quality of Informed Consent Questionnaire, taken 1 week and 1 month later, and scored using a consensus-based algorithm. Participants also completed the Center for Epidemiologic Studies Depression Scale. Data analyses were conducted on 129 patients and caregivers (t-tests, Fisher's exact tests, and ANCOVAs).
Results: T-tests showed no significant differences in comprehension and recall between depressed and nondepressed participants at 1 week and 1 month. However, ANCOVA showed patients with a support person present had significantly higher comprehension and recall at 1 week but not at 1 month compared with controls. Caregivers present with a patient had lower comprehension/recall than those without a patient present (p = 0.02).
Conclusions: Having a support person present during the informed consent process helps depressed PD patients better retain information in the short-term, but effects diminish over the long-term. Implications for interventions will be discussed.