Effect of on-site facilities on use of diagnostic radiology by non-radiologists.

This study uses self-reports from a nationwide sample of 5447 physicians in ten medical and surgical specialties to assess the impact of on-site facilities on the use of radiologic examinations by non-radiologists. Data from 169,559 patient visits show that when on-site radiologic facilities are available to non-radiologists, radiographs increase by a factor of 1.2 (internal medicine) to 1.7 (pediatrics). Use of radiologic examinations is up to four times greater for hospitalized compared with nonhospitalized patients and is slightly higher for hospital-based physicians and for younger physicians.