2024 Yes https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD015029.pub2/full Littlecott, Hannah North America Europe Review Teachers Staff Students Elementary (K-5) Middle/Jr High (6-8) High School (9-12) Ventilation rates The 15 main studies consisted of measures to reduce contacts (4 studies), make contacts safer (7 studies), surveillance and response measures (6 studies; 1 assessed transmission outcomes, 5 assessed performance of surveillance measures), and multicomponent measures (1 study). These main studies assessed outcomes in the school population (12), general population (2), and adults living with a school?attending child (1). Settings included K?12 (kindergarten to grade 12; 9 studies), secondary (3 studies), and K?8 (kindergarten to grade 8; 1 study) schools. Two studies did not clearly report settings. Studies measured transmission?related outcomes (10), performance of surveillance measures (5), and intended and unintended consequences (4). The 15 main studies were based in the WHO Region of the Americas (12) and the WHO European Region (3). Comparators were more versus less intense measures, single versus multicomponent measures, and measures versus no measures. We organized results into relevant bodies of evidence, or groups of studies relating to the same 'intervention?comparator?outcome' categories. Across all bodies of evidence, certainty of evidence ratings limit our confidence in findings. Where we describe an effect as 'beneficial', the direction of the point estimate of the effect favours the intervention; a 'harmful' effect does not favour the intervention and 'null' shows no effect either way.