背景：全民健保開辦之後，台灣整體壽命增加，對健康不平等貢獻似乎不多，其貢獻主要在有助改善急性病之健康不平等，然而對癌症等慢性病在不適用的指標下有相反結果。本研究旨在以預期壽命研究不同收入區域間之口腔癌健保前後改變。
方法：台灣癌症登記檔中病理診斷為口腔鱗狀細胞癌者納入分析，再串聯死亡登記檔做存活分析，分別定義1990-1994、1998-2007新發個案為健保前、後族群；以縣市平均家庭可支配所得作為指標分為3組。用半母數外推方式計算預期壽命，並以台灣生命表為對照組，將病患以性別、年齡、年代配對計算預期壽命損失，並以Z檢定差異。
結果：整體而言健保後預期壽命增加，口腔癌男性健保前皆為6.5年，健保後依收入區域高中低為13.0、13.1、11.8年；女性健保前依收入區域為14.9、13、4.6年，健保後則為16.3、15.4、13.3年。不論性別、收入組別，健保後預期壽命損失皆有下降；男性不論收入區域高中低預期壽命損失下降皆達到統計顯著，分別是6.79、3.83、2.65年，女性低收入區域預期壽命損失下降6.94年，達統計顯著。不同收入區域之間口腔癌存活在健保後無顯著差異。
結論與建議：在健保之後不同收入區域間預期壽命損失差異降低，癌症對族群健康影響主要來自發生率差異，建議消除健康不平等須從預防工作著手。

Background
Thanks to the universal coverage of National Health Insurance (NHI), life expectancy gained. However, whether the insurance system contributes to health inequality, especially among cancers, is not yet been proved. The aim of this study is to measure health inequality before and after implementation of NHI and to test the hypothesis that NHI reduces health inequality.
Material & Method
Patients diagnosed with oral squamous cell carcinoma in the Taiwan Cancer Registry were included. Cities and counties were ranked according to Survey of Family Income and Expenditure and then grouped into 3 income and area related classes. The survival curve of index population is extrapolated and life expectancy (LE) is estimated by a semi-parametric method. Age- sex- and calendar year- matched reference populations were generated from life table, and expected years of life lose (EYLL) were calculated.
Results
After NHI, life expectancy improves and expected years of life lose decreases among all oral cancer patients. For male groups, EYLL decreases from about 2.65 to 6.79 years. And the EYLL difference between female groups eliminates. There is no significant disparity on oral cancer survival.
Conclusion
After implementation of National Health Insurance, incidence may contribute to health impact. Prevention may play an essential role in reducing health inequality.

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