Changes in Outpatient Imaging Utilization and Spending Under a New Population-Based Primary Care Payment Model

Area of Science:

• Health economics
• Primary care policy
• Medical imaging utilization

Background:

• Hawaii Medical Service Association (HMSA) implemented a new payment model, Population-Based Payments for Primary Care (3PC).
• Understanding the impact of alternative payment models on healthcare spending and utilization is crucial for healthcare reform.

Purpose of the Study:

• To evaluate the association between the 3PC payment system and changes in outpatient imaging spending and utilization.
• To assess the first-year impact of the 3PC model on healthcare resource allocation.

Main Methods:

• Observational study using claims data from 2012-2016.
• Propensity-weighted difference-in-differences analysis comparing 3PC-participating and fee-for-service groups.
• Primary outcome: total outpatient imaging spending; secondary outcomes: spending and utilization by modality.

Main Results:

• The 3PC system showed no significant association with overall outpatient imaging spending.
• A statistically significant decrease in nuclear medicine spending (-20.1%) and utilization (-18.1%) was observed.
• Most secondary outcomes did not show statistically significant changes.

Conclusions:

• The HMSA 3PC payment model did not lead to significant overall changes in outpatient imaging costs in its first year.
• The observed reduction in nuclear medicine services suggests a potential impact on specific imaging modalities.
• Further research is needed to understand the long-term effects and broader implications of this payment model.