Highly Stable Beneficiary Attribution in Medicare's Comprehensive Primary Care Plus Model

Area of Science:

• Health Services Research
• Primary Care Policy
• Healthcare Economics

Background:

• Advanced primary care models enhance accountability for patient care quality and costs.
• Beneficiary attribution methodology is crucial for model design and practice payments.
• Stable attribution encourages long-term investment in advanced primary care.

Purpose of the Study:

• To evaluate attribution stability for Medicare fee-for-service beneficiaries in the Comprehensive Primary Care Plus (CPC+) Model.
• To assess the impact of attribution methodology on practice payments and investment.

Main Methods:

• Calculated annual churn rates (percentage of beneficiaries attributed to a different practice) from 2017-2021 CPC+ data.
• Analyzed attribution stability for overall CPC+ beneficiaries and specific subgroups.
• Assessed attribution responsiveness to beneficiary practice changes, including long-distance moves.

Main Results:

• Overall annual attribution churn rate was 12%, with 70% of beneficiaries attributed to the same practice after four years.
• Vulnerable subgroups, such as disabled beneficiaries, experienced higher churn rates.
• Attribution changes for long-distance movers occurred after an average of five quarters.

Conclusions:

• High attribution stability in CPC+ likely fostered practice investment in advanced primary care.
• Addressing churn in vulnerable populations is essential for equitable advanced primary care.
• Consistent beneficiary attribution is key to the success of value-based care models.