PROJECT SUMMARY Post-acute care in skilled nursing facilities (SNFs) is common, and outcomes are poor and variable. Over the past decade, SNFs have been a target of efforts to improve outcomes while controlling spending, but robust gains remain elusive. Our prior work showed that the number of physicians who specialize in SNF-based care (i.e., “SNFists”) grew rapidly over the past decade. In this study, we will examine whether physicians specializing in SNF-based care improve functional outcomes and reduce potentially avoidable healthcare utilization (such as hospital readmissions) of patients receiving post-acute care in SNFs. We will also examine patient functional outcomes and healthcare utilization of SNFists vs. non-SNFists under value-based purchasing initiatives. To accomplish these goals, we will expand an existing dataset of Medicare claims and SNF clinical assessment data for Medicare fee-for-service beneficiaries discharged from an acute care hospital to a SNF from 2012 through 2018. Using this database, we will examine the trends in physician specialization in SNF care in the context of value-based purchasing (i.e., whether the discharging hospital participated in bundled payments or an Accountable Care Organization), market competition, and other market and physician characteristics. Next, we will measure the impact of physician specialization in SNF care on patient outcomes and potentially avoidable healthcare utilization using difference-in-differences cross-temporal matching. Lastly, we will conduct semi-structured interviews with key personnel (e.g., director of nursing) in SNFs to quantitatively identify training, practice strategies and care processes that differ between physicians who specialize in SNF care and those who do not. When complete, these studies will inform practice and policy to optimize (increase or reduce) post-acute care patients' access to physicians who specialize in SNF-based care.