Informed adherence: the need for shared medical decision making.

Screening tests for colon cancer, breast cancer, and elevated serum cholesterol are widely advocated and included in some practice guidelines. Failure to complete these tests is regarded as patient noncompliance. The purpose of this paper is to review noncompliance with screening tests from the perspective of a traditional biomedical model and an outcomes model. According to the traditional biomedical model, compliance with screening tests is necessary to identify disease at an early stage and to initiate treatment. In contrast, the outcomes model argues that patients and providers should engage in activities that maximize benefit from the patient's perspective. Screening may lead to significant increases in case identification and in treatment rates. However, screening might also identify "pseudodisease," defined as disease that is not clinically important. For some diagnostic tests, cases of pseudodisease far exceed cases of clinically meaningful disease. The outcomes model suggests shared medical decision making in which uncertainties surrounding tests are disclosed to patients. Using information about the risks and expected health outcomes of screening and treatment, patients can participate in decisions about their own health care. Control Clin Trials 2000;21:233S-240S