The characteristics of physician practices joining the early ACOs: looking back to look forward

To assess whether the characteristics and capabilities of individual practices intending to join the early Medicare accountable care organization (ACO) programs differed from those of practices not intending to join.

Data from a 2012-2013 national survey of 1398 physician practices were linked to 2012 Medicare beneficiary claims data to examine differences between practices intending to join a Medicare ACO and practices not intending to join a Medicare ACO.

Differences were examined with regard to patient sociodemographic characteristics and disease burden, practice characteristics and capabilities, and cost and quality measures. Logistic regression was used to examine the differences.

Practices intending to join were more likely to have better care management capabilities (odds ratio [OR], 1.72; P <.003), health information technology functionality (OR, 1.87; P <.001), and use of quality improvement methods (OR, 1.52; P <.04). They were also more likely to have had prior pay-for-performance experience (OR, 1.59; P <.02) and less likely to be physician-owned (OR, 0.51; P <.001). However, the practices with the greater capabilities still used half or less of them.

Physician practices that intended to join the early ACO programs had greater capabilities and experience to manage risk than those practices that decided not to join. The early ACO programs thus attracted the more capable physician practices, but those practices still fell short of implementing key recommended behaviors. The findings have implications for future physician practice selection into ACOs.