Secular Trend in the Incidence of Conduct Disorder in China from 1990 to 2019: A Joinpoint and Age-Period-Cohort Analysis

The aim of this study was to analyze the secular trends of conduct disorder (CD) incidence in China from 1990 to 2019 under the joinpoint analysis and the age-period-cohort framework.The sex-specific incidence rates of CD from 1990 to 2019 were extracted from the Global Burden of Disease Study 2019 database according to the age group. The joinpoint regression and the age-period-cohort model were conducted using the average annual percent changes and relative risks as size effects, respectively.From 1990 to 2019, age-standardized rates (ASRs) of CD incidence showed an overall increasing trend in both sexes, and this variation trend was observed in almost all age groups. The annual sex-specific ASRs were lower in China than those worldwide but were rapidly growing. Age effects were the most significant risk factor for CD, with the highest risk in adolescents aged 10 to 14 years, followed by children aged 5 to 9 years, but a relatively lower risk in adolescents aged 15 to 19 years than in other age groups. However, period and cohort effects were not statistically significant.CD incidence rates in China have been increasing in both sexes from 1990 to 2019. Further studies are necessary to explain the etiology of these increases and promote the early identification of individuals at risk for developing CD.