This study investigates the impact of online gambling on problem behaviors among South Korean adolescents across three phases of the COVID-19 pandemic: pre-pandemic (2018), early pandemic (2020), and late pandemic (2022). We applied a doubly robust estimation approach that combines propensity score matching with regression analysis using nationally representative survey data from the Korea Problem Gambling Agency. Our findings indicate that online gambling significantly intensified adolescents' problem behaviors in all periods, with a more pronounced effect observed during the late pandemic phase in 2022 compared to the early phase in 2020. Sensitivity analysis further demonstrated that the estimated effects were substantially robust to unobserved confounding, particularly in 2018 and 2022. We conclude with a discussion of adolescents' heightened vulnerability to online gambling-related problem behaviors and the corresponding need for targeted interventions and policy responses.
Park et al. (Sat,) studied this question.