Share of Diagnostic Imaging Interpretation: Radiology and Other Specialties

The aim of this study was to examine radiology's and other specialties' market shares for diagnostic imaging interpretation for Medicare fee-for-service claims by modality, body region, and place of service.

In this cross-sectional study of Physician/Supplier Procedure Summary data for 2022, the authors examined the proportion of diagnostic imaging interpretation by specialty. All claims for CT, MR, nuclear medicine (NM), ultrasound, and radiography and fluoroscopy (XR) were included. Claims were aggregated into 52 specialty groups using Medicare specialty codes. The market share for each specialty group was computed by modality, body region, and place of service.

For Medicare fee-for-service beneficiaries, there were 122,851,716 imaging studies, of which 88,559,272 (72.1%) were interpreted by radiologists. This percentage varied by modality: 97.3% for CT, 91.0% for MR, 76.6% for XR, 50.9% for NM, and 33.9% for ultrasound. Radiologists interpreted a lower percentage of cardiac (67.6% for CT, 42.2% for MR, 11.8% for NM, and 0.4% for ultrasound) than noncardiac studies (97.6% for CT, 91.4% for MR, 95.6% for NM, and 53.0% for ultrasound). Among noncardiac studies, radiologists interpreted nearly all in the outpatient hospital, inpatient, and emergency department (99.5% for CT, 99.4% for MR, 98.9% for NM, 79.3% for ultrasound, and 97.9% for XR) compared with the office setting (84.4% for CT, 78.7% for MR, 85.4% for NM, 29.2% for ultrasound, and 43.1% for XR).

Radiologists perform the dominant share of CT and MR interpretation and more so for noncardiac imaging and imaging performed in outpatient hospital, inpatient, and emergency department places of service.