Supply-side variation in the use of emergency departments

We study the role of person- and place-specific factors in explaining geographic variation in emergency department utilization using detailed data on 150,000 patients who moved regions within Israel. We document that about half of the destination-origin differences in the average emergency department utilization rate across districts translates to the change (up or down) in movers' propensity to visit the emergency department. In contrast, we find no change in the probability of having a hospital admission through the emergency department. Similar results are obtained in a complementary event study, which uses hospital entry as a source of variation. The results from both approaches suggest that supply-side variation in emergency department access affects only the less severe cases-for which close substitutes likely exist-and that variation across emergency physicians in their propensity to admit patients is not explained by place-specific factors, such as differences in incentives, capacity, or diagnostic quality.