text: Prevalence of mental health problems among children and adolescents during the COVID 19 pandemic A systematic review and meta analysis This systematic review and meta analysis examined the prevalence of depression anxiety sleep disorders and posttraumatic stress symptoms among children and adolescents during global COVID 19 pandemic in 2019 to 2020 and the potential modifying effects of age and gender A literature search was conducted in PubMed Web of Science PsycINFO and two Chinese academic databases China National Knowledge Infrastructure and Wanfang for studies published from December 2019 to September 2020 that reported the prevalence of above mental health problems among children and adolescents Random effects meta analyses were used to estimate the pooled prevalence Twenty three studies 21 cross sectional studies and 2 longitudinal studies from two countries i e China and Turkey with 57 927 children and adolescents were identified Depression anxiety sleep disorders and posttraumatic stress symptoms were assessed in 12 13 2 and 2 studies respectively Meta analysis of results from these studies showed that the pooled prevalence of depression anxiety sleep disorders and posttraumatic stress symptoms were 29 95 CI 17 40 26 95 CI 16 35 44 95 CI 21 68 and 48 95 CI 0 25 1 21 respectively The subgroup meta analysis revealed that adolescents and females exhibited higher prevalence of depression and anxiety compared to children and males respectively All studies in meta analysis were from China limited the generalizability of our findings Early evidence highlights the high prevalence of mental health problems among children and adolescents during the COVID 19 pandemic especially among female and adolescents Studies investigating the mental health of children and adolescents from countries other than China are urgently needed 