近年來，台灣醫療支出不斷擴張，經濟發展卻幾見負成長，本研究旨在檢視不同因素對醫療保健支出成長率的影響以及不同所得家戶的醫療安全差距變化，以供健保改革政策參考。本研究利用Schieber and Poulier的分解方法，假設名目醫療保健支出受醫療保健物價、人口數量等因素影響，殘值為醫療保健質量。利用健保保障率及受益率兩指標，分析不同所得族群之醫療安全變化；所有原始資料來自政府部門公開統計及家庭收支調查。結果顯示：（1）21世紀以來，名目醫療保健支出年增率4.49%，主要來自醫療通貨膨脹（2.43%）及人口老化（1.68%）；調整人口老化後醫療保健質量的成長幾乎呈現停滯。（2）隨著自付醫療費用增加，全民健保的保障率由68%下降至66%。（3）雖然就健保受益率而言，窮人仍舊受益最多（5.27至5.05倍），但家戶所得越高，健保給付增加越快（2.13至2.33倍），現在貧富之間的醫療安全差距已相對擴大。建議未來政府在推動健保改革時，應重視醫療品質的確保，通貨膨脹的影響以及醫療安全差距擴大的挑戰。

Taiwan's healthcare expenditures have increased in recent years despite occasional periods of negative growth in national income. This study examined the contributions of price, population, and volume-intensity to the growth of healthcare spending, and the change in healthcare expenditure security across income groups. We followed the method of Schieber and Poulier to break down the growth of nominal national healthcare spending into increases in healthcare prices and population. Volume-intensity was calculated as a residual and was affected by aging of the population. Healthcare expenditure security was defined by the rate of National Health Insurance (NHI) coverage and the benefit-premium ratio, and was compared across income quartiles. All data were based on public government statistics and the Survey of Family Income and Expenditure. Results indicated that: (1) Since the beginning of the 21th century, nominal growth in health care spending has stayed around 4.49% and came mainly from health care inflation (2.43%) and population aging (1.68%). Volume-intensity grew sluggishly. (2) The NHI coverage rate declined from 68 to 66% with an increase in out-of-pocket spending. (3) In terms of the benefit-premium ratio, NHI remained generally pro-poor (5.27 to 5.05 times); however, disparity in healthcare security widened because the NHI benefit-premium ratio increased faster for the rich (2.13 to 2.33 times). We suggest that future NHI reform should focus on quality assurance, the effects of inflation, and equity in healthcare security.