October 23, 2020

Spillover effects of payment systems

 Randomized trial shows healthcare payment reform has equal-sized spillover effects on patients not targeted by reform

From PNAS: 

Changes in the way health insurers pay healthcare providers may not only directly affect the insurer’s patients but may also affect patients covered by other insurers.

This is the research question. And this is the result:

We use a payment reform in TM, which was randomly applied to some markets but not others, to study spillovers of healthcare payment reform. We find spillovers of the same sign and similar magnitude on privately insured MA patients. Naturally, our findings are specific to our setting; the existence, sign and magnitude of any spillovers may well vary across contexts.

Sounds good. However, there is a previous research question, which is the insurer's market share that allows to have the option to change the payment system. This former question is as relevant as the later one.