Importance: Use of health care services and physician practice patterns have been shown to vary widely across the United States. Although practice patterns-in particular, physicians' ability to provide high-quality, high-value care-develop during training, the association of a physician's regional practice environment with that ability is less well understood.
Objective: To examine the association between health care intensity in the region where physicians practice and their ability to practice high-value care, specifically for physicians whose practice environment changed due to relocation after residency.
Design, setting, and participants: This cohort study included a national sample of 3896 internal medicine physicians who took the 2002 American Board of Internal Medicine initial certification examination followed approximately 1 decade (April 21, 2011, to May 7, 2015) later by the Maintenance of Certification (MOC) examination. At the time of the MOC examination, 2714 of these internists were practicing in a new region. Data were analyzed from March 6, 2016, to May 21, 2018.
Exposures: Intensity of care in the Dartmouth Atlas hospital referral region (HRR), measured by per-enrollee end-of-life physician visits (primary) and current practice type (secondary).
Main outcomes and measures: The outcome, a physician's ability to practice high-value care, was assessed using the Appropriately Conservative Management (ACM) score on the MOC examination, measuring performance across all questions for which the correct answer was the most conservative option. The exposure, regional health care intensity, was measured as per-enrollee end-of-life physician visits in the Dartmouth Atlas HRR of the physician's practice.
Results: Among the 3860 participating internists included in the analysis (2030 men [52.6%]; mean [SD] age, 45.6 [4.5] years), those who moved to regions in the quintile of highest health care intensity had an ACM score 0.22 SD lower (95% CI, -0.32 to -0.12) than internists who moved to regions in the quintile of lowest intensity, controlling for postresidency ACM scores. This difference reflected scoring in the 44th compared with the 53rd percentile of all examinees. This association was mildly attenuated (0.18 SD less; 95% CI, -0.28 to -0.09) after adjustment for physician and practice characteristics.
Conclusions and relevance: This study found that practice patterns of internists who relocate after residency training appear to migrate toward norms of the new region. The demands of practicing in high-intensity regions may erode the ability to practice high-value conservative care.