雖然台灣從1995 年開始實施全民健保制度，減輕了民眾在使用醫療資源上的財務負擔，但是位於偏遠山區或是離島的居民卻仍然空有保險，而無處看病，導致醫療可近性存在城鄉差距。因此，健保署也逐步實施偏鄉醫療計畫以改善偏遠地區醫療資源不足的問題，其中於民國88 年起實施的「全民健康保險山地離島地區醫療給付效益提昇計畫」（Integrated Delivery System, IDS），藉由導入偏鄉外的醫療資源與整合當地醫療院所與山地離島鄉衛生所，改善偏鄉地區整體健保醫療服務品質。本研究使用1996 至2006 年健保資料庫中，偏鄉地區病患資料，利用差異中差異分析法，估計參與計畫之鄉鎮在IDS 計畫實施前後兩年可預防住院的變化。實證結果發現位於台灣西半部地區的IDS 計畫之鄉鎮，在IDS 計畫實施之後有顯著的降低可預防住院的發生，而對於住院醫療費用也有節制的效果存在。然而，位於台灣東半部地區的IDS 計畫之鄉鎮，在IDS 計畫實施之後反而有增加可預防住院發生的趨勢，而可預防住院醫療費用也有提高的現象，隱含當地可能存在未獲滿足的醫療需求（unmet medical need），而在經過醫療介入之後，當地醫療資源的增加正好滿足了當地病患的醫療照護需求量。;Despite the fact that Taiwan has implemented National Health Insurance (NHI) at 1995, there′s still some people who live in rural areas have obstacles to access medical care. In order to improve the accessibility of medical care, the Department of the Health and Welfare successively implemented the integrated delivery system (IDS for short) programs which appoint local hospitals to regularly offer ambulatory care to the residents living in different remote areas since 1999. This research selects patients reside in rural areas and its neighbor townships from 1996-2006 National Health Insurance Database and uses difference-in-difference technique to evaluate the IDS policy effect on preventable hospitalization. We found that rural townships in the west of Taiwan have lower rate of preventable hospitalization as well as the hospitalization expenditures after the implementation of the IDS plan. By contrast, the rural townships in the east of Taiwan have the opposed effects, that is the IDS program will increase the rate of preventable hospitalization and its expenditures. This may imply that the IDS may substitute inpatient care for ambulatory care for the residents in remote township in the east.
