{"p"=>"Psychological and behavioral interventions for insomnia are increasingly recognized as promising approaches not only to improve sleep but also to influence mental health outcomes in children and adolescents. This systematic review and meta-analysis examined the effects of insomnia-focused psychological and behavioral interventions on depressive symptoms, with particular attention to potential across selective and indicated prevention as well as adjunctive treatment contexts. A comprehensive literature search was conducted in PubMed/MEDLINE, PsycINFO, the Cochrane Library, and major Chinese databases (CNKI, Wanfang) from inception to December 30, 2025. Randomized controlled trials comparing psychological or behavioral insomnia interventions with control conditions and reporting changes in depressive symptoms in children and adolescents were included. Random-effects meta-analyses, meta-regression analyses, and within-arm standardized mean change analyses were performed. Eight studies comprising 904 participants (mean age=13.46 years) were identified. Across all studies, depressive symptoms improved from baseline to post-intervention, with a significant overall benefit of insomnia-focused interventions compared with control conditions (SMD=0.238, 95% CI=0.088–0.387, p=0.0019). Within-arm analyses indicated that effects in passive-comparator studies reflected genuine intervention benefit rather than spontaneous remission. Subgroup analyses showed no significant moderation by delivery format or setting, including digital interventions. The high intervention completion rate across trials (87%) supports the potential of insomnia as an indirect, less-stigmatizing entry point for depression prevention in children and adolescents — consistent with frameworks proposing that targeting comorbid, causally linked conditions may reduce depressive symptoms while lowering barriers to engagement. Integrating evidence-based insomnia interventions into clinical, school-based, and digital settings could substantially extend the reach of early mental health strategies."}