Abstract
To understand how clinicians with high caseloads of socially at-risk patients fare under Medicare's new outpatient Merit-based Incentive Payment System (MIPS), we examined the first (2019) round of MIPS performance data for 510,020 clinicians. Compared with clinicians with the lowest socially at-risk caseloads, those with the highest had 13.4 points lower MIPS performance scores, were 99 percent more likely to receive a negative payment adjustment, and were 52 percent less likely to receive an exceptional performance bonus payment. The lower performance scores were partly explained by lower clinician reporting of and performance on technology-dependent measures, which may reflect a lack of practice-level technological capability. If the Complex Patient Bonus were in effect, the performance scores and likelihood of receiving an exceptional performance bonus (payment of clinicians with the highest socially at-risk caseloads) would have increased by 4.7 percent and 2.8 percent, respectively; however, the proportion receiving negative payment adjustments would have remained unchanged. The Complex Patient Bonus appears unlikely to mitigate the most regressive effects of MIPS.