2025 Yes https://doi.org/10.1080/16549716.2025.2466896 Jahan, Farjana Asia Observational Epidemiology Study Students Teachers Elementary (K-5) Middle/Jr High (6-8) High School (9-12) Water quality Absenteeism Cognative function School wash Sanitation and hygiene Wash facilities Environmental hygiene Bangladesh Using 2014/2018 surveys, this study found Bangladeshi schools improved access to safe water (78–90%) and sanitation (19–52%). Gaps remain, especially in government and rural schools, highlighting need for targeted WASH interventions.