Examines staff size and composition of the 496 advanced primary care practices participating in CMS's comprehensive primary care initiative, in 7 regions (states or local areas) that were selected for the demonstration.

Participating practices all have electronic health records, submitted applications to participate in this demonstration program designed to improve primary care practices, and were selected as the most advanced of the applicants in terms of use of health information technology and certification as a medical home or possessing features similar to those of a medical home. Participating practices will receive monthly payments from Centers for Medicare & Medicaid (CMS) for Medicare patients attributed to the practice, and from other payers in the market taht are participating in the initiative. The demonstration began in October 2012 and will continue for 4 years. This early paper focuses on describing these practices at the outset of the demonstration.

Inclusion Criteria:

• All Medicare fee-for-service patients who receive the majority of their Evaluation and Management visits from one of the study practices.

Exclusion Criteria:

• none.

Medicare patients enrolled in traditional Medicare who receive the majority of their Evaluation and Management visits from one of the study practices.

not allowed; data belong to the federal government