What Attitudes and Beliefs Underlie Patients' Decisions about Participating in Chemotherapy Trials?

Abstract

The theory of reasoned action, which postulates that personal attitudes and external social influences predict intentions to undertake a behavior, was used as a conceptual framework for developing a questionnaire to elicit beliefs and attitudes associated with the decision to participate in a hypothetical cancer chemotherapy trial. After completing the questionnaire, two-thirds of the 150 respondents indicated they would enroll in such a trial if it were available. Considerable variation existed in both "universal" and "trial- specific" beliefs and attitudes underpinning their intentions. A substantial amount of the variance in "intention" to participate was explained by "attitude" alone (75%). So cial influences, although statistically significant, made a mere 1% additional contribu tion. One interpretation is that subjective expected-utility theory, which essentially pre dicts beliefs or "attitude," is a better model. The authors conclude that both theories may be criticized regarding how well they capture the rationality and nuances of de cision behavior. Key words: attitudes; beliefs; clinical trials; oncology. (Med Decis Mak ing 1998;18:61-69)