Effects of extending residencies on the supply and quality of family medicine practitioners; difference‐in‐differences evidence from the implementation of mandatory family medicine residencies in Canada
利用加拿大各省分阶段实施强制延长家庭医学住院医师培训的政策，发现该政策使初级医疗提供者数量在9年内下降5%，尤其影响年轻医生，但未改善医生质量（以公开谴责衡量）。
I examine the impacts of extending residency training programs on the supply and quality of physicians practicing primary care. I leverage mandated extended residency lengths for primary care practitioners that were rolled out over 20 years in Canada on a province-by-province basis. I compare these primary care specialties to other specialties that did not change residency length (first difference) before and after the policy implementation (second difference) to assess how physician supply evolved in response. To examine quality outcomes, I use a set of scraped data and repeat this difference-in-differences identification strategy for complaints resulting in censure against physicians in Ontario. I find declines in the number of primary care providers by 5% for up to 9 years after the policy change. These changes are particularly pronounced in new graduates and younger physicians, suggesting that the policy change dissuaded these physicians from entering primary care residencies. I find no impacts on quality of physicians as measured by public censure of physicians. This suggests that extending primary care training caused declines in physician supply without improvement in the quality of these physicians. This has implications for current plans to extend residency training programs.