Comprehensive Primary Care Plus Did Not Improve Quality Or Lower Spending For The Privately Insured.

Comprehensive Primary Care Plus (CPC+) was a multipayer payment reform model that provided incentives for primary care practices to lower spending and improve quality performance. Although CPC+ has been evaluated in Medicare, little is known about its impact in the private sector. Using claims and enrollment data from the period 2013-20 from two large insurers in Michigan, we performed difference-in-differences analyses and found that CPC+ was not associated with changes in total spending (-$44.70 per year) or overall quality performance (-0.1 percentage point). These changes did not vary systematically across CPC+ cohorts, tracks, regions, or participation in prior primary care innovations. We conclude that CPC+ did not improve spending or quality for private-plan enrollees in Michigan, even before accounting for payouts to providers. This analysis adds to existing evidence that CPC+ may cost payers money in the short term, without concomitant improvements to care quality.