Diagnostic Tests

Abstract

Until about 100 years ago, the history and physical examination were the only sources of information available to the clinician confronted with a diagnostic decision. He was thus limited to what he could see, hear, feel, smell, or taste — in other words, to what his own senses could tell him. The development of radiology and bacteriology around the turn of the century enabled him to amplify and extend his sensory input. More recently, with the refinement of sophisticated radiographic, biochemical, and immunologic techniques, the diagnostic test has become an invaluable tool in the detection and definition of disease.