Changes in subjective well-being among Korean adolescents, 2016-2021: A nationwide panel survey study

<i>Background:</i> Subjective well-being (SWB) has been a popular topic in positive psychology and mental health, representing how individuals experience and evaluate their lives.<i>Objective:</i> This study aimed to determine the SWB of Korean adolescents and its change over time.<i>Method:</i> We utilised data from the Korean Children and Youth Well-being Index: Middle School and High School Students Surveys, collected from 2016 to 2021. Bivariate analyses were performed to estimate SWB, and analysis of variance was used to assess differences in SWB based on participant characteristics. Changes in SWB over time were analysed using mean difference values, with subgroup analyses comparing middle and high school students.<i>Results:</i> Findings revealed that while overall SWB remained relatively stable from 2016 to 2019 (with scores of 72.47 and 71.68, respectively), a significant decrease was observed in 2021 (scoring 68.97). Notably, SWB was significantly lower in females compared to males, and in high school students compared to middle school students. A consistent downtrend in SWB was evident over the five years among specific groups, including females, adolescents not living with their parents, those intending to leave home, and those experiencing severe stress.<i>Conclusions:</i> This study examined the SWB of Korean adolescents and its change over time, revealing a significant decline in 2021 during the COVID-19 pandemic. These findings underscore the importance of monitoring SWB and having informed welfare initiatives to enhance adolescents' quality of life. The insights remain relevant, guiding policymakers in preparing for future pandemics and improving SWB among vulnerable adolescents.