The adequacy of comprehension of the information needed for informed consent to participate in research on spouse responses to a husband's or wife's general surgery was assessed. Comprehension of information about the research study by 75 spouses was measured by the Informed Consent Questionnaire containing questions on study purpose, time involvement, nature of participation, risks, benefits, voluntariness, confidentiality, and anonymity. The result showed that 72 of the 75 spouses had adequate comprehension of the information for informed consent. Because adequate comprehension is atypical of most studies, possible reasons for this unexpected result are discussed and then explained within a self-determination theory of informed consent.