Physician performance of laboratory tests in self-service facilities. Residents' perceptions and performance.

Primary care physicians perform simple laboratory tests in clinical practice, frequently with little formal training. To determine the frequency of tests that are performed and evaluate house officer laboratory skills, we surveyed house officer attitudes and tested their ability to perform four common laboratory tests. We received 193 responses from 254 house officers at one university teaching hospital. While most perceived the need to use ward laboratories (ie, self-service laboratories located on patient care wards), 67% used them infrequently. Barriers included poor laboratory condition, inadequate time, accuracy, and infectious exposure concerns. Twenty-four percent felt they did not know or were unsure if they knew how to perform simple tests. Forty-seven house officers completed the practical examination. Most accurately reported a spun hematocrit and correctly identified white blood cell findings on a blood smear. Only 50% counted 100 cells. Urinary dipstick interpretation was generally acceptable but the microscopic examination was less accurate. Twenty-three percent failed to identify gram-negative rods on a slide with both gram-positive cocci and gram-negative rods. If physicians are to perform selected laboratory tests, these data suggest, at least in one institution, more formal training, practice, and evaluation are necessary to ensure their performance with adequate proficiency.