Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Estimates of the impact of Certificate of Need (CON) laws on medical care have been inconsistent, possibly because not all CON laws apply to all services. Using an original dataset identifying imaging-related CON laws and a regression discontinuity design at state borders, we estimate the effects of CON on the use and quality of diagnostic imaging. Medicare beneficiaries in regulated states are less likely to receive any image and even less likely to receive low-value imaging than beneficiaries in unregulated states. High-value imaging is unaffected. Overall, CON for imaging reduces low-value care and leaves high-value care unchanged.