Diagnostic testing in obstetrics and gynecology: a clinician's guide.

As we enter a new era of health care in the United States with limited economic resources, there will be an increasing demand for thoughtful and critical evaluation of the diagnostic tests used in clinical medicine. To interpret the clinical utility of diagnostic tests, the physician must understand the fundamental concepts of sensitivity, specificity, and predictive values. The purpose of this paper is to define these terms, demonstrate the use of receiver operating characteristic curves and Bayes' theorem, and provide clinical examples in obstetrics and gynecology to illustrate their use. Practitioners must be able to interpret the results of diagnostic tests to provide accurate information to their patients.