The "Abnormal" Screening Laboratory Results

Abstract

Increasing use of the automated chemical screening battery has magnified a problem which formerly was rare: what to do with an unexpectedly "abnormal" laboratory result. To assess the response of physicians to the appearance of a laboratory value outside the stipulated range of normal and its significance to patients, we reviewed computer-stored clinical data with written records of 547 patients seen in the Stanford University Hospital Medical Clinic. We found that physicians tended to pay little attention to "abnormal" results of screening battery laboratory tests, which, furthermore, led to positive diagnoses only infrequently during the period of observation of this sample of patients. Deviation from normal has both statistical and clinical meanings and can result from a variety of causes, of which the physician must be aware in order to make reasonable judgements.