Avoidable, amenable, and preventable mortalities in South Korea, 2000-2017: Age-period-cohort trends and impact on life expectancy at birth.

This study aimed to estimate age-period-cohort effects on avoidable mortality and quantify the impact of avoidable mortality changes on life expectancy (LE) at birth in the South Korean population aged 0-74 years. Using death certificate and resident population data from 2000 to 2017, trends in age-standardized avoidable mortality rates were analyzed with joinpoint regression. Intrinsic estimator regression analysis was conducted to estimate age-period-cohort effects on avoidable mortality. Arriaga's method was used to measure the contributions of avoidable causes to changes in LE gaps between adjacent three-year periods by age and avoidable cause of death groups. Avoidable mortality decreased annually by 4.6% between 2000 and 2017. There were strong age and cohort effects and a weak period effect on avoidable mortality. In the overall decreasing trend, avoidable mortality declined less in cohorts born after the 1950-1953 Korean War and economic recession in the 1970s, with further reductions in cohorts born after the 1987 democratic reform and 1997-1998 economic crisis. Avoidable mortality was reduced after implementation of major health policies, but the decrease stagnated during the 2008-2009 financial crisis. Avoidable mortality reduction resulted in LE gains of 3.1 years, which accounted for 80% of total LE gains. Contribution to LE gains by causes of death was the largest for cerebrovascular disease. Major social changes and health policies influenced the avoidable mortality trend through cohort and period effects. Health care and public health policies implemented since the 2000s might have contributed substantially to gains in LE.