Jonathan H. Sunshine

BACKGROUND: To assess possible differences in physicians' practices with respect to diagnostic imaging, we compared the frequency and costs of imaging examinations as performed by primary physicians who used imaging equipment in their offices (self-referring) and as ordered by physicians who always referred patients to radiologists (radiologist-referring). METHODS: Using a large, private insurance-claims data base, we analyzed 65,517 episodes of outpatient care by 6419 physicians for acute upper respiratory symptoms, pregnancy, low back pain, or (in men) difficulty urinating. The respective imaging procedures studied were chest radiography, obstetrical ultrasonography, radiography of the lumbar spine, and excretory urography, cystography, or ultrasonography. RESULTS: For all four clinical presentations, the self-referring physicians obtained imaging examinations 4.0 to 4.5 times more often than the radiologist-referring physicians (P less than 0.0001 for all four). For chest radiography, obstetrical ultrasonography, and lumbar spine radiography, the self-referring physicians charged significantly more than the radiologists for imaging examinations of similar complexity (P less than 0.0001 for all three). The combination of more frequent imaging and higher charges resulted in mean imaging charges per episode of care that were 4.4 to 7.5 times higher for the self-referring physicians (P less than 0.0001). These results were confirmed in a separate analysis that controlled for the specialty of the physician. CONCLUSIONS: Physicians who do not refer their patients to radiologists for medical imaging use imaging examinations more frequently than do physicians who refer their patients to radiologists, and the charges are usually higher when the imaging is done by the self-referring physician. From our results it is not possible to determine which group of physicians uses imaging more appropriately.

PURPOSE: To assess the most recent available data for levels and trends in utilization of radiology procedures across populations, modalities, and geographic areas. MATERIALS AND METHODS: Aggregated claims data from Medicare enrollees for all radiology procedures and from the Medical Expenditure Panel Survey (MEPS), a nationally representative survey of almost 25 000 Americans, for some radiology procedures, were used to calculate population-based utilization for the relevant age groups. Limited private insurer data also were obtained. All radiology utilization was measured and reported, irrespective of provider specialty. Average levels and percentiles of utilization were measured according to modality, and average annual rates of increase in utilization were compared across modalities, data sources, and regions. Rates of increase in utilization according to modality and state were compared for correlation with state characteristics and initial utilization levels. RESULTS: In 2001, 4176 diagnostic and 274 therapeutic radiology procedures were performed per 1000 Medicare non-managed care enrollees. Nearly one-half of diagnostic procedures (n=2057) involved radiography. The other half involved computed tomography (CT) (n=391), magnetic resonance (MR) imaging (n=114), ultrasonography (US) (n=921), interventional radiology (n=215), mammography (n=221), and nuclear medicine (n=249). On average, between 1998 and 2001, utilization per Medicare enrollee increased 16% per year for MR imaging and 7%-15% per year for CT, US, interventional radiology, and nuclear medicine, while that for radiography increased 1% per year. The proportion of diagnostic radiology procedures performed in ambulatory settings increased from 62% in 1992 to 68% in 2001. There was wide variation across states in utilization by Medicare enrollees. State totals for diagnostic radiology were 3038 in the 10th percentile and 4573 in the 90th percentile. In 1999, MEPS reported average utilization in ambulatory settings as follows: 64 MR imaging, 102 US, 73 mammographic, 326 radiographic, and 43 radiation therapy procedures per 1000 persons (all ages) in the U.S. population. CONCLUSION: Utilization of high-technology modalities increased rapidly, while that of radiography was relatively stagnant. Variation in utilization among states and census regions was substantial.

PURPOSE: To determine radiologists' workloads in 2006-2007, as measured by both procedures per full-time equivalent (FTE) radiologist and relative value units (RVUs) per FTE radiologist, and to discover trends since 1991-1992. MATERIALS AND METHODS: Non-individually identifiable data from the American College of Radiology (ACR) 2007 Survey of Radiologists were compared with data from previous ACR surveys; all surveys were weighted to make them nationally representative. Under National Institutes of Health rules for protection of human subjects, studies based on anonymized surveys do not require approval by an institutional review board. Workload according to individual practice characteristics, such as type (eg, academic, private, multispecialty) and setting, was tested for statistically significant differences from the average for all radiologists. Time trends and the independent effect on workload of practice characteristics were measured with regression analyses. Changes in average procedure complexity were calculated in physician work RVUs per Medicare procedure. RESULTS: In 2006-2007, the average annual workload per FTE radiologist was 14,900 procedures, an increase of 7% since 2002-2003 and 34.0% since 1991-1992. Annual RVUs per FTE radiologist were 10 200, an increase of 10% since 2002-2003 and 70.3% since 1991-1992. Academic practices performed about one-third fewer procedures per FTE radiologist than others. In most types of practice, radiologists in a 75th-percentile practice performed at least 65% more procedures annually than radiologists in a 25th-percentile practice. Regression analysis showed that practices that used external off-hours teleradiology services performed 27% more procedures than otherwise similar practices that did not use these services. CONCLUSION: Radiologists' workload continued to increase in recent years. Because there is much unexplained variation, averages or medians should not be used as norms. However, such statistics can help practices to understand how they compare with other, similar practices. SUPPLEMENTAL MATERIAL: http://radiology.rsnajnls.org/cgi/content/full/2522081895/DC1.

PURPOSE: To evaluate spinal injection procedures for trends in volume, reimbursement, and physician specialty participation. MATERIALS AND METHODS: By using the 1993, 1996, 1998, and 1999 Medicare Part B claims database, we studied Current Procedural Terminology revision 4 codes used for percutaneous spinal injection procedures, including cervical and lumbar discography, disk aspiration and/or injection, facet and/or perifacet joint injection, and epidural steroid injection. For each of these procedures, volume, reimbursement, and physician specialty participation (categorized as radiology, anesthesiology, surgery, physiatry, and other specialties) for each year were recorded. RESULTS: Despite an overall increase in spinal injection procedure volume and reimbursement from 1993 to 1999, nonradiologists performed most of these procedures. Epidural steroid and facet joint injections had the highest volume and reimbursement during this time period and were performed almost exclusively by nonradiologists (predominantly anesthesiologists). Radiologists performed more discography procedures than did other specialists in 1993, but participation decreased each year, while anesthesiologist participation increased; as of 1999, anesthesiologists performed more discography procedures than did radiologists. Although radiologists performed more disk aspiration procedures than did other specialists, procedure volume remained low during the period studied. CONCLUSION: Spinal injection volume and reimbursement have increased substantially in the Medicare population from 1993 to 1999. During this interval, radiologist participation has decreased. Nonradiologists perform most spinal injection procedures.