Computed Tomography Volumes from 2,398 Radiology Practices in the United States:A Realtime Indicator of the Effect COVID-19 on Routine Care, January to September 2020

Davenport, Matthew S.; Fruscello, Tom; Chatfield, Mythreyi; Weinstein, Stefanie; Sensakovic, William F.; Larson, David B.

Purpose To determine the effect of coronavirus disease 2019 (COVID-19) on CT volumes in the United States during and following the first wave of the pandemic. Methods CT volumes from 2,398 United States radiology practices participating in the American College of Radiology (ACR) Dose Index Registry from January 1, 2020 to September 30, 2020 were analyzed. Data were compared to projected CT volumes using 2019 normative data, and analyzed with respect to time since government orders, and population-normalized positive COVID-19 tests and attributed deaths. Data were stratified by state population density, unemployment status, and race. Results There were 16,198,830 CT examinations (2,398 practices). Volume nadir occurred an average of 32 days after each state-of-emergency declaration and 12 days after each stay-at-home order. At nadir, the projected volume loss was 38,043 CTs per day (of 71,626 CTs/day; 53% reduction). Over the entire study period, there were 3,689,874 less CT examinations performed than predicted (of 18,947,969; 19% reduction). There was less reduction in states with smaller population density (15% [169,378/1,142,247; Quartile 1] vs. 21% [1,894,152/9,140,689; Quartile 4]) and less reduction in states with a lower insured unemployed proportion (13% [279,331/2,071,251; Quartile 1] vs. 23% [1,753,521/7,496,443; Quartile 4]). By September 30, CT volume had returned to 84% (59,856/71,321) of predicted; recovery of CT volume occurred as positive COVID-19 tests rose and deaths were in decline. Conclusion COVID-19 substantially reduced United States CT volume, reflecting delayed and deferred care, especially in states with greater unemployment. Partial volume recovery occurred despite rising positive COVID-19 tests.