Shared medical decision-making: a new paradigm for behavioral medicine--1997 presidential address.

Different conceptual models lead to different health care choices. The traditional biomedical model emphasizes identification of pathology (diagnosis) and remediation of these biological deficits (treatment). An alternative approach, known as the outcomes model, focuses attention on the outcomes of health care. Specifically, health care is regarded as effective only if it extends life or if it improves quality of life. Indices that combine life expectancy and life quality can be used to monitor the benefits of health care. According to the traditional model, medical care is effective if it improves a clinical indicator (i.e. reduces blood pressure, decreases tumor size, etc.). According to the outcomes model, treatments are not advocated unless they improve general outcomes. There are circumstances in which clinical indicators improve but general outcomes remain the same or get worse. Data on the detection and treatment of prostate cancer are used to illustrate how these models might lead to different treatment decisions. According to the traditional model, aggressive screening and treatment of prostate cancer should be advocated because more cases are detected early and more tumors are removed. According to the outcomes model, net quality-adjusted life may be reduced rather than enhanced with screening. Shared medical decision-making is an outgrowth of the outcomes model. Using these methods, patients and providers integrate the best scientific evidence on treatment efficacy with patient preferences for outcomes. Often shared decision-making leads to reductions in the use of medical procedures.