AUTHOR=Dou Kai-yun , Dong Ru-bao , Gan Chun-long TITLE=The impact of COVID-19 pandemic on sleep duration and mental health among middle school students: a 3-year cross-sectional survey JOURNAL=Frontiers in Public Health VOLUME=13 YEAR=2025 URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2025.1482309 DOI=10.3389/fpubh.2025.1482309 ISSN=2296-2565