Background: The informed consent process for research warrants improvement but approaches designed to enhance informed consent need testing in the context of actual clinical research. Purpose: Test the cumulative effect of a retrospective quality assurance questionnaire intended to enhance awareness in the person obtaining informed consent on the quality of the informed consent in clinical trials. Methods: In the Veterans Affairs Cooperative Study 'Enhancing the Quality of Informed Consent- Self Monitoring', 30 study sites are randomly assigned from five clinical trials to either use a new quality assurance questionnaire after each informed consent encounter or the standard process of obtaining informed consent. The quality of informed consent is evaluated using independent telephone interviews of 836 subjects who had given consent to participate in the clinical trials and the authors' study. The main outcome measures are two previously validated scores derived from an independent telephone interview, measuring the overall quality of consent as well as the degree of 'therapeutic misapprehension'. Patients and assessors are blind to the study arm assignment. Results: Subjects report complete (93%) or some (6%) satisfaction with the consent process of the 'parent' clinical trial, and 91% recognize no consequences to non-participation. Concerning the 'primary purpose' of the parent trial, 67% indicate understanding of the research purpose, 41% that the research is to benefit others, while 14% think the research is directed to their own benefit; 60% report no risk to participation and 65% report at least one expects direct benefit. Interviewers assess 77% of subjects as showing full appreciation of the 'voluntariness' of participation. The quality assurance questionnaire do not provide an appreciable effect on the quality of informed consent. Using mixed model methods to account for the group randomization, near zero, non-significant effects have been found for the overall assessment score (-0.034 on a 0-10 point scale, standard error 0.099, P = 0.73) and for the score measuring 'therapeutic misconception' (-0.005 on a 0-5 point scale, standard error 0.137, P = 0.97). Permutation methods yield similar results. Confidence intervals are narrow enough to exclude any clinically important effect. Limitations: The intervention may work in a more homogeneous patient population, or one that is not sampled. The outcome measurement relies on a short, anonymous, telephone interview (to minimize burden and eliminate bias), but a longer, face-to-face interview may be more sensitive to differences. A 'checklist' tied directly to the outcome measures may show an effect. Conclusions: Despite prior beliefs, a standardized quality assurance tool do not enhance informed consent in actual clinical trials. Future research is needed to rigorously evaluate proposed methods to enhance informed consent prior to widespread introduction.
Copyright 2008 Elsevier B.V., All rights reserved.