Our new study was published yesterday online in the American Journal of Public Health.  We analyzed the effects of the 1966 Medicare/Medicaid and the 2014 Affordable Care Act coverage expansions on the utilization of physician services — both visits and procedures.  We found that although these coverage expansions redirected care to the newly covered, they did not increase overall society-wide use.   Considered together with our study of how these expansions affected hospital utilization (together with other work on the utilization effects of Canadian single-payer, the NHS, and pre-ACA Medicaid expansions), this research suggests that estimates of the cost of coverage expansions may often be in error.