Cognitive interviewing as a tool for improving the informed consent process.

Consent materials often contain complex information, legalese, and other features that render them difficult to comprehend in such a way that consent is truly informed. I propose that researchers adapt cognitive interviewing, normally used for the pretesting of survey questionnaires, to evaluate the understandability of consent materials and the way which subjects use this information to make decisions regarding participation. Cognitive interviewing involves the intensive probing of small samples of volunteer subjects to elucidate thought processes that otherwise remain hidden. Cognitive interviewing can be applied: (a) to further the basic science of informed consent; (b) to pretest materials for a specific study; and (c) as embedded procedure for assessing subject thought processes in the course of obtaining consent.