Margaret M. Holmes

Comparison of physicians' decisions regarding estrogen replacement therapy for menopausal women and decisions derived from a decision analytic model

Decisions regarding estrogen replacement therapy were obtained from 50 physicians for 12 cases representing menopausal women with systematically varying levels of cancer risk, fracture risk, and symptom severity. Their decisions were compared with a decision analytic model for which each physician provided needed quantities--subjective probabilities, utilities of various outcomes, and weightings of the importance of the outcome categories. The majority of observed decisions were not to treat. By contrast, the decision analysis based on physician-provided estimates indicated that the optimal strategy was either to treat or a toss-up. Sensitivity analysis showed that these conclusions would hold over all possible utilities, over all plausible probabilities of cancer, and so long as symptom relief and fracture prevention were also considered as treatment objectives. The increased probability of early detection of cancer by regular follow-up was systematically incorporated into the decision analysis but apparently neglected in unaided clinical judgment, which follows the principle of minimizing the most important risk, regardless of its probability.

Women’s and physicians’ utilities for health outcomes in estrogen replacement therapy

Estrogen replacement therapy (ERT) prevents fractures and relieves vasomotor symptoms, but it increases the risk of endometrial cancer. Previous studies and national prescribing patterns show that physicians are conservative in their approach to this therapy. The authors interviewed physicians and perimenopausal women to assess their utilities for the various health outcomes of estrogen replacement therapy. On all outcomes, physicians rated illness episodes followed by recovery as being closer to perfect health than did perimenopausal women. Physicians, in judging which outcomes were most important to women, estimated relief of symptoms above fracture prevention, whereas women rated fracture prevention above symptom relief. These results emphasize the need to assess patients’ utilities directly, particularly when utilities for the outcome of a particular therapy may influence the choice of a therapeutic regimen.

Medical Decisions in Perspective: Applied Research in Cognitive Psychology

Medical decisions claim the attention ofthose outside the scientific and medical communities as well as of their members. The general pubUc has an abiding concern in the personal and economic consequences ofmedical decisions. Researchers are engaged in analyzing medical decisions and determining the information necessary for action under uncertainty and the impact of high technology on decision making. For these reasons, clinical decision making has become a major area for psychological investigation. The rapid growth of research in clinical decision making has led to interest in improved methods and frameworks for data analysis. The purpose of this paper is to describe and evaluate the primary theories and methods employed in contemporary psychological research on clinical decision making and to compare these approaches with two naturalistic methods of research in this field, chart audit and direct observation. The findings from this body of research wUl not be summarized here since several recent reviews are readUy avaUable [1-4]. Psychological research on medical decision making has generally been experimental or controlled research. Subjects respond to a carefully designed or selected medical problem, either a written or simulated case in an experimental setting. This design results in highly reproducible, reliable information but is subject to question about the relationship of these results to the real world. More naturaUstic studies, relying on patient charts or observation in clinical settings, are clearly related to die real world but may produce results that are so much a function of time and

Factors affecting laboratory utilization in clinical practice.

Recent work in decision analysis and cost-effectiveness suggests that there exists an optimum workup for a particular presenting problem, based on the prior likelihood of a specific diagnosis and the cost of missing a specific diagnosis. We have studied the relation between a specified optimum set of laboratory studies in patients presenting with the complaint of hirsutism and the laboratory studies ordered by a single practicing physician over a period of five years. Although a laboratory testing protocol had been developed by this physician, implying an optimal workup, signifi-