Tiered network health plans and changes in physician practice intensity

To examine whether physicians in tiered physician networks where tier assignments are based on "intensity" of care, which is the quantity of resources used per-episode of care, change their intensity after learning detailed information about how their intensity compares to their peers.

Administrative data on intensity and quality at the physician-episode level for all physicians included in a tiered physician network offered through the Massachusetts Group Insurance Commission (GIC) in 2010-2015. Data on physicians' share of revenue from GIC patients from the 2012 Massachusetts All-Payer Claims Database.

For 21,086 physicians in seven specialties, we estimate the impact of the dissemination of detailed intensity performance information in 2014 on physician intensity per episode of care overall and decomposed into physician services, facility, and pharmaceutical subcomponents. Intensity outcomes were measured using a standardized price schedule. Using a difference-in-differences regression, we compared physicians with high exposure to the tiered network via a large share of their revenue coming from GIC patients ("GIC share") to physicians who were less exposed. Measures of intensity of care and GIC share were log-transformed, and models controlled for physician-episode type fixed effects.

We linked GIC share to administrative data using National Provider Identifier.

There were no statistically significant differences in total intensity of care with the informational intervention for physicians in procedure-based specialties (-0.12 elasticity of intensity per episode with respect to GIC patient share, 95% CI -0.30 to 0.06) or in relationship-based specialties (0.09, 95% CI -0.15 to 0.33). There were also no differences in intensity of subcomponents of care following the intervention.

Tiered network incentives had no detectable impact on intensity of care that physicians provided to patients.