Medicare implemented Bundled Payments for Care Improvement (BPCI) Model 3 in 2013, in which participating skilled nursing facilities (SNFs) were accountable for episode costs. We performed comparative interrupted time series analyses to evaluate associations between SNF BPCI participation and nurse staffing levels, using Medicare claims, resident assessments, and facility-level and market-level files of 2010–2017. For persistent-participating SNFs, BPCI was associated with improved certified nursing assistant (CNA) staffing levels (differential change = .03 hours, p =...