In-Classroom physical activity breaks (IcPAB) are a promising way to promote children’s health behaviors, while contributing to the development of their academic and cognitive ability and health outcomes. Yet the effect of the activity breaks, which are exclusive to classroom settings, are still mixed and unclear. Hence, this review was conducted to identify the characteristics and the effects of IcPAB among primary school children. The review protocol was registered on PROSPERO (CRD42021234192). Following the Cochrane guidelines, PubMed, PsycINFO (ProQuest), MEDLINE (EBSCOhost), Embase/Ovid, SportDISCUS (EBSCOhost), Web of Science, Scopus and Academic Search Premier (EBSCOhost) databases were searched to collect data on randomised control trials without a time restriction. The final database search was conducted on the 8 November 2021. Random effects models were used to calculate the effect sizes. The systematic review identified ten eligible studies, nine of which were also included in the meta-analysis. Few studies used the theoretical frameworks and process evaluations. IcPAB showed mixed effectiveness on academic outcomes: i.e., IcPAB had effects on spelling performance (p < 0.05) and foreign language learning (p < 0.01) but not on mathematics and reading performance. Health behaviors such as moderate-to-vigorous physical activity levels were improved (p < 0.01), but IcPAB did not have an impact on cognition outcomes and health outcomes. Given these mixed results, further research is needed underpinned by strong methodological quality, theoretical underpinnings and reliable process evaluation methods.

Purpose: The purpose of this review was to synthesize the empirical evidence of relevant studies related to preventive behaviors in response to the COVID-19 pandemic among children and adolescents. Further to this, we aimed to identify the demographic, psychological, and social and environmental correlates of such behaviors.Methods: Following PRISMA guidelines, eligible literature was identified by searching seven databases (PsycINFO, PubMed, MEDLINE, EMBASE, Cochrane Library, PROSPERO registry platform, and ClinicalTrials.gov website) and reference list of included studies and relevant review papers from 1^stJan 2020 to 28^thFeb 2021. The standardized mean difference and correlation coefficientsrwere extracted to estimate the effect sizes. Analyses were conducted using R software.Results: Of the 35,271 original papers, 23 eligible studies were included in the qualitative synthesis and all these studies were of moderate-to-high quality, of which 17 studies were further included into the quantitative analysis. Children and adolescents (6–20 yrs.) showed a poorer practice of COVID-19 preventive behaviors compared to younger adults (21–59 yrs.) with a small-to-medium effect size (SMD = -.25, 95%CI = -.41 to -.09). For the demographic correlates, children and adolescents’ COVID-19 preventive practice was found to be significantly associated with gender (r = .14, 95%CI = .10 to .18), while not with age (r = -.02, 95%CI = -.14 to .10). Narratively, knowledge was found to be consistently and significantly correlated. For the psychological correlates, small-to-medium overall effects were identified for the association with attitudes (r = .26, 95%CI = .21 to .31) and perceived severity (r = .16, 95%CI = .01 to .30). For the family and social correlates, a non-significant association was identified between family economic status and COVID-19 preventive behaviors (r = .004, 95%CI = -.12 to .12).Conclusions: Interventions and relevant policies of promoting children and adolescent’s preventive measures should be a priority. Further, empirical studies identifying the demographic, psychological, and family and social correlates of children and adolescents’ preventive behaviors are needed.