全民健康保險實施前後醫院權屬別與市場競爭對醫療成效之影響

Abstract

本研究利用全民健康保險（健保）實施前後之勞工保險住院檔再探醫院權屬別與醫院競爭是否影響醫療成本與品質，並檢定健保後其影響是否出現結構性變化。結果以工具變數估計發現非營利醫院長期醫療品質較佳；使用細分之權屬別分析則發現不同公立體系醫院的醫療成效有著很大差異。另外鄒檢定結果指出健保後醫院權屬別對醫療成效影響的確出現結構性變化，其中私立醫院在健保後成本較高、醫療品質較佳，而非營利醫院在健保後短期死亡率較高。最後本研究使用「差異之中的差異法」發現健保後醫院競爭程度之減少皆使得醫療費用顯著上升，且長期和短期醫療品質並無顯著影響，此結論明顯與醫武競賽之理論不符。然而，本研究進一步發現健保後醫院規模愈大，費用與死亡率的確愈低。由此觀之，醫院競爭有可能反映於醫院規模而非市場集中度之層面。

This paper reexamines the effect of hospital ownership and competition on hospital outcomes before and after the National Health Insurance (NHI) using the labor insurance inpatient data. The results of IV estimation indicate that non-profit hospitals yield better long-term quality in medical care, yet there are differences in the effect on the outcomes among several public hospital systems when using more detailed ownership data. Furthermore, the results of Chow Test show that the effect of hospital ownership has a structural break after the NHI, which implies more cost and better treatment quality in private hospitals and higher long-term mortality in non-profit hospitals. On the other hand, the decrease in hospital competition after the NHI enhances the treatment expenditure and has no significant effect on the mortality, which is inconsistent with the Medical Arm Race (MAR) hypothesis. However, we find that the larger scale of hospitals does yield less treatment expenditure and mortality after the NHI, implying that the competition may reflect on the scale of hospitals instead of the market concentration.