Comparison of laboratory test use among three urgent care clinics.

Laboratory test ordering practices among physicians at three walk-in or urgent-care medical facilities were compared to evaluate the relationship between practice type and test ordering patterns. The charts of 221 patients were reviewed for test ordering as an aid for the diagnosis of cough or upper respiratory infection (169 patients) or diarrhea (52 patients). For upper respiratory infections, the free-standing walk-in clinic ordered the greatest number of tests; and for both categories of disease, the urgent care unit of a health maintenance organization (HMO) ordered the fewest tests.