This study examines four methods of paying practices that operate as medical homes.  They study considers "enhanced fee-for-service payments for evaluation and management; additional codes for medical home activities within fee-for-service payments; per patient per month medical home payments to augment fee-for-service visit payments; and risk-adjusted, comprehensive per patient per month payments." 

Merrell, K. and Berenson, R. A. (2010) Structuring payment for medical homes. Health Affairs 29(5): 852-858. doi: 10.1377/hlthaff.2009.0995 http://content.healthaffairs.org/cgi/content/abstract/29/5/852 

Authors: Katie Merrell and Robert A. Berenson.