Decision making about treatment of hypothetical prostate cancer: Is deferring a decision an expert-opinion heuristic?

Men diagnosed with prostate cancer must make decisions about medical treatment in a context of high uncertainty. However, when making decisions about treatment, many men prefer to defer decision-making responsibility to their physician. Because the reason has not been explained well, an exploratory study investigated the effect of varying ambiguity and risk and relevant psychological and sociodemographic variables on men's desire for involvement in decision making in a hypothetical treatment scenario. A self-report questionnaire was administered by mail to a community sample of 705 men who were part of an ongoing study into men's health. Measures included the Multidimensional Health Locus of Control scale, the Revised Scale for Ambiguity Tolerance, and the Desire for Involvement Scale. In addition, the men were randomly allocated to four experimental groups for a 2 x 2 manipulation of high and low ambiguity with high and low risk for one of four scenarios for choices of treatment. Varying risk and ambiguity did not affect men's desire for involvement in decision making. Deferral of decision-making responsibility to the physician was predicted by high powerful others (p <.0001), low internal locus of control, a preference for black-and-white thinking, and lower levels of education (p's <.05). The results provided preliminary support for the conceptualization of deferral of decision-making responsibility to the physician as a shortcut-the expert-opinion heuristic.