Clinical decision-making in the face of scientific uncertainty: hormone replacement therapy as an example.

There is widespread variation in the prescribing patterns of postmenopausal hormone replacement therapy. While some degree of variation is expected, the systematic variation according to geographic region, physician gender, and medical specialty raises questions about how clinical decisions are made. This paper explores the determinants of these practice patterns, specifically the contribution of patients' preferences, scientific uncertainty, and physicians' recommendations. A role for collaborative decision-making is described and the use of decision-support tools is discussed. The primary care setting is proposed as the ideal context in which to study collaborative decision-making. Additional research is needed to more fully elucidate the value of collaborative decision-making with respect to clinical and quality-of-life outcomes, patient satisfaction with decision-making, and costs.