全民健保實施對社經狀況不同地區的國民死亡率影響之研究──以時間數列分析

Socioeconomic status differences in ‘avoidabl’ mortality under national health insurance in Taiwan: Time series analysis

背景： 我國政府自1995年3月起開辦全民健康保險，此一重大衛生政策對國人的醫療健康照護影響深遠，在全民強制納保的措施下，許多學者的研究指出，確實使國人就醫之可近性大幅提升，尤其是全民健保開辦前未能參加健康保險的民眾。對於全民健保相關議題，先前國內的研究與調查大多著重於醫療利用率及滿意度的評估，而以可避免死因死亡率動態資料的縱貫研究，尚不多見。本研究係利用區域別全死因死亡率與可避免死因死亡率，在10年間(1992-2001) 的動態變化，來探討全民健保政策介入對於國人健康情形的影響。目的： 本研究的目的，在於探討全民健保實施對於社經狀況不同地區的國人健康狀況之影響。材料： 1992~2001年「臺灣地區居民死亡資料檔」，行政院衛生署。1992~2001年「中華民國臺灣地區家庭收支調查報告」，行政院主計處。1991~2001年「中華民國臺閩地區人口統計」，行政院內政部。方法： 本研究以「全死因死亡率及可避免死因死亡率」做為健康情形之測量。利用不同社經狀況地區自1992年1月至2001年12月期間（此間包含全民健保實施前後）的標準化死亡率之變動數列，以介入模式進行分析比較。由數列變動的形態能反映出全民健保實施的影響。結果： 研究結果發現，全民健保的實施對於高所得地區以及低所得地區之全死因死亡率具顯著下降之影響；可避免死因死亡率方面，研究結果兩地區都沒有顯著降低的影響。結論： 高所得地區死亡率漸進改變量約降低0.93（每十萬人），低所得地區約降低1.40（每十萬人），顯示全民健保實施對低所得地區居民健康的影響效應較佳，可能是原本健康狀況較差的低所得地區之民眾因可近性的增加，得以獲得較好的醫療照護所致。

Context: The implementation of the National Health Insurance (NHI) in Taiwan on March 1,1995 has profound impact on our health care system. Many studies have pointed out that the NHI tremendously increases our compatriots’ accessibility to medical services, particularly those who did not being insured before. In addition, many other researches, focusing on the assessment of satisfaction with the NHI’s services. Although, findings of those studies are interesting, there were few studies addressed the potential influence of the increasing access resulted from the NHI on people’s health status. The NHI ‘s potential and differential impacts on the health status of our compatriots deserve an investigation. Purpose: To compare the changes of health status (using mortality and avoid mortality as measures) for people who live in different geographical areas, with different socio-economic status before and after the implementation of the NHI. By examining the changes, the potential and differential impacts can be attributed to the NHI. Method：The all-cause mortality and avoidable mortality were used as the indicators to measure the health status. Mortalities for people lived in different geographical areas and of different socio-economic status as well as age groups were standardized for comparison. The event intervention analysis was employed to assess the movement of monthly data of all-cause and avoidable mortality rate from January 1992 to December 2001. Because the data includes the mortality before and after the implementation of NHI, patterns of change in mortality could reflex the effects result from NHI. Results：The findings of this study reveal that all-caused mortality declined significantly after the implementation of NHI; regardless of the geographical areas, socioeconomic status, and age groups. Additionally, compared to people with higher income, the magnitude of the reduction in all-cause mortality tend to be higher for those with lower income. On the other hand, decline of avoidable mortality for people lived in different geographical areas, with different socio-economic status, and of different age groups are found to be statistically insignificant after the implementation of NHI. Conclusion：Change in mortality indicates that the implementation of NHI tend to have a stronger positive impact on the health status for people with lower income level. It possibly because of the accessibility for people with low income has better improved. The implications suggest that there are for further improvement can be aimed at some vulnerable groups.