Prevalence of Pediatric Autism Spectrum Disorder in Korea Using National Statistics Including the COVID-19 Pandemic, 2011 to 2021

Purpose: Regularly analyzing the prevalence of autism spectrum disorder (ASD) is important to inform policies and strategies for proper management. The present study aimed to esti-mate trends in ASD prevalence according to age and time in Korean children. Methods: We monitored the annual prevalence of ASD in children aged 2 to 18 years based on information from Statistics Korea and the Korean National Health Insurance Service. We estimated changes in prevalence between 2011 and 2021 after stratifying partici-pants into three age groups. Furthermore, we analyzed the prevalence of ASD by birth year. Results: The highest level of prevalence appeared in children aged 6 years, and thereafter, it declined with age. The prevalence of ASD in children aged 2 to 18 years increased from 0.05% in 2011 to 0.12% in 2021. During the same time, the prevalence in preschool children (2 to 5 years) remarkably increased from 0.04% in 2011 to 0.12% in 2021, while the prevalence in adolescents (13 to 18 years) increased from 0.05% in 2011 to 0.09% in 2021. The prevalence of ASD notably increased during the coronavirus disease 2019 (COVID-19) pandemic (2020 to 2021). Among children born between 2011 and 2015, the prevalence of ASD was higher for children with recent birth years, especially during the COVID-19 pandemic. Conclusion: The overall ASD prevalence in children and adolescents in Korea seems to be increasing, especially in preschool children during the COVID-19 pandemic. Early and more effec-tive interventions are necessary for Korean children. © 2023 Korean Child Neurology Society.