Double Scan CT Rates: An Opportunity for Facility-Based Radiologist Measures in the Quality Payment Program

Abstract

PurposeThe Medicare Access and CHIP Reauthorization Act (MACRA) provides CMS flexibility to evaluate radiologists using hospital outpatient quality measures in place of conventional physician measures. We explore radiologist characteristics associated with variation in performance in two such measures: abdomen and chest CT “double scan” rates (percentage of total examinations performed both with and without intravenous contrast). MethodsRadiologists’ claims for abdomen and chest CT examinations in a facility setting were identified using 2014 Medicare Physician and Other Supplier data. Individual radiologist double scan rates were computed. Associations were explored between rates and radiologist characteristics extracted from the CMS public data sets using multivariable regression with cross-validation. ResultsRadiologists’ double scan rates averaged 5.9% ± 10.0% (0.0% for 52.8% of radiologists) for abdomen CT (19,867 radiologists) and 1.0% ± 4.7% (0.0% for 91.3% of radiologists) for chest CT (18,684). At multivariable analysis, abdomen rates were best predicted by geography (lowest in Northeast, greatest in West), practice size (greatest for small practices), and specialty practice pattern (lowest for general radiologists; greatest for nuclear medicine physicians). Agreement for double scan rates among radiologists within the same practice was moderate, though slightly higher for chest (intraclass correlation = 0.70) than abdomen (0.59). ConclusionRadiologists’ facility double scan rates vary systematically based on an array of professional characteristics. MACRA grants CMS the authority to use these measures for evaluating radiologists, thereby aligning Medicare’s hospital and physician performance programs and better incentivizing population radiation dose and cost reduction. Greater variation in abdomen CT double scan rates, compared with ubiquitously excellent chest CT performance, supports a particular role for abdomen rates in distinguishing disparities in radiologist performance.