Conclusions
SECONDARY
In this cohort study, across the broader context of deteriorating mental health in UK students, we observed that the COVID-19 pandemic considerably exacerbated this trend. We also identified individual, home, friendship, and school characteristics that were associated with changes in mental health difficulties and mental well-being. These findings have policy implications, suggesting that students’ risk and resilience should be conceptualized as multidimensional, including individual, family, friendship, and school factors. Future interventions need to consider all of these levels to effectively address the increasing mental health challenges faced by secondary school students.