The usefulness of x-ray examinations in the evaluation of patients with back pain.

Process and outcome data from 440 patients with back pain were analyzed. As a part of their care, 106 patients (24 percent) had back x-ray examinations. The non-x-rayed group of patients was used as a naturally occurring control group to determine what contribution back radiographs made to the cost, to the diagnoses and therapeutic decisions of providers, and to the outcome and satisfaction of patients. Although back x-rays contributed more to the cost of patient care than any other diagnostic study, their contribution to diagnosis was minimal, and had little effect on therapeutic decisions. Patients receiving back x-rays were more likely to have had prolonged symptoms at their first visit, and less likely to be symptom-free at four weeks, but were more likely to be satisfied with their care. The authors conclude that, for patients under 50, back x-ray examinations have negligible diagnostic value and their use could be reduced without decreasing the quality of medical care.