Comparison of Secular Trends in Road Injury Mortality in China and the United States: An Age-Period-Cohort Analysis

This study aimed to identify and compare the mortality trends for road injuries in China and the United States, and evaluate the contributions of age, period, and cohort effects to the trends from 1990 to 2014. Using the 2016 Global Burden of Disease Study database, the mortality trends were analyzed by joinpoint regression and age-period-cohort modeling. Overall, the mortality for road injuries was higher in China than in the United States. The mortality in China increased from 1992 to 2002 (annual percent change [APC] was 1.9%), and then decreased from 2002 to 2015 (APC(2002-2009) was 1.5%; APC(2009-2015) was 3.5%). For the United States, the mortality decreased from 1990 to 2010 (APC(1990-1997) was 1.8%; APC(1997-2005) was 0.7%; APC(2005-2010) was 4.2%). Age-period-cohort modeling revealed significant period and cohort effects. Compared with the period 2002-2004, the period risk ratios (RRs) in 2010-2014 period declined by 14.62% for China and 18.86% for the United States. Compared with the 1955-1959 birth cohort, the cohort RRs for China and the United States in the 2010-2014 cohort reduced by 47.60% and 75.94%, respectively. Period and cohort effects could not be ignored for reducing road injury mortalities.