By clearly describing commonly performed tests including many blood and urine tests, nuclear scans, scoping techniques, biopsies, and taps, the physician-authors perform an outstanding service in removing the mysteries surrounding these procedures. For each test there is an explanation of why it is performed, what advance preparations are needed, the procedure itself, how the patient will actually feel, the risks involved, the significance of the results, and an approximate cost. Self-diagnostic tests are also outlined in a special section. The authors urge patients to ask questions about any proposed test. Responsibility for one's own health is the hallmark of this informative book. Carol R. Glatt, Helene Fuld Medical Ctr. Lib., Trenton, N.J.