目標：分析機動車事故與台灣城鄉平均餘命差距之相關性。方法：自衛生署、內政部、交通部及主計處取得人口、死因登記、各類機動車輛登記數及事故等資料，將22個縣市根據都市發展程度劃分為鄉村和都市地區，使用平均餘命分因法計算機動車事故對於平均餘命之量化影響，並以逐步廻歸分析法(Stepwise regression models)進行平均餘命及機動車事故相關因子之分析。結果：都市地區之出生時平均餘命為76.1年至80.8年，鄉村地區為71.6年至77.6年，其中機動車事故影響了0.2年至0.5年及0.6至1.1年。城鄉平均餘命差距最大者為9.2年，機動車事故死亡率之差距對於平均餘命差距之貢獻度為4.0%至16.2%。機動車事故死亡率較高之地區，其平均餘命明顯較短(r＝-0.87, p＜0.01)，且機動車事故死亡率之差距明顯影響平均餘命差距(Partial R2＝0.75,p＜0.0001)，城鄉因素為機動車事故死亡率最具影響力之因子(Partial R2＝0.66,p＜0.0001)，而重型機車為唯一對於機動車事故死亡率具顯著影響之車輛(Partial R2＝0.03, p＜0.0001)。結論：機動車事故擴大台灣各縣市及城鄉平均餘命之差距，減少機動車輛密度及事故將對弱勢鄉村地區人口之平均餘命助益最大。

Objectives:To explore the differential impact of urban and rural areas on motor vehicle accidents(MVA) and life expectancy in aiwan.Methods:Data for population,death registration,income, and motor vehicle registration were acquired from the government. Life expectancy(LX)and itsgains after MVA deaths were eliminated were calculated for Taiwan as a whole and for each city and county. Stepwise Regression Models were used to examine the association of MVAwith the gap in LX. Results: Residents in most of the rural areas had a shorter LX,ranging from 71.6 to 77.6 years, than did urban residents whose LX ranged from 76.9 to 80.8 years.MVA mortality contributed 4.0% to 16.2% of the gaps in LX between Taipei City and each of the counties or cities.The impact of MVA on LX ranged from 0.6 to 1.1 years in ruralareas and from 0.2 to 0.5 years in urban areas. MVA mortality was signifcantly negatively correlated with life expectancy (r=-0.87, p<0.01) and infuenced the gaps in LX (Partial R2
=0.75, p<0.0001).
Urbanization was the most important factor in reducing MVA mortality(Partial R2=0.66,p<0.0001) and heavy motorcycle was the only signifcantly infuential motor vehicle on MVA mortality (Partial R2
=0.03, p<0.0001). Conclusions: Motor vehicle accidents were responsible
for the worsening health disparity between urban and rural areas in Taiwan. The rural suffered a higher impact from motor vehicle density and its associated accidents on life expectancy than their urban counterparts. Reducing motor vehicle accidents would most beneft the life expectancy of populations in rural areas.