National trends in alcohol and substance use among adolescents from 2005 to 2021: a Korean serial cross-sectional study of one million adolescents.

"Declarations Conflict of interestNo financial or non-financial benefits have been received or will be received from any party related directly or indirectly to the subject of this article.  Ethical approvalThe KYRBS data were anonymous and the study protocol was approved by the Korean Centers for Disease Control and Prevention Agency (KCDA) and Institutional Review Board of Sejong University (SJU-HR-E-2020-003). Conflict of interest No financial or non-financial benefits have been received or will be received from any party related directly or indirectly to the subject of this article. "

"Funding This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HV22C0233 and grant number: HI22C1976). The funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report."