How different is California? A comparison of U.S. physician organizations.

Data from a national study of medical groups and independent practice associations are used to examine the extent to which California physician organizations are different from physician organizations in the rest of the United States. California physician organizations are different in many ways: most notably, they are more likely to have external incentives to improve quality and more likely to use recommended care management processes for treating patients with chronic illnesses. The implications of these differences for policy and practice are discussed.