2024 Yes https://doi.org/10.1186/s12916-024-03558-x Bick, Sarah Africa Experimental Students Elementary (K-5) Middle/Jr High (6-8) Water quality Absenteeism Respiratory symptoms Infections School health Hand hygiene Water Respiratory illness Diarrhoea School absence Ethiopia A cluster-randomised trial in 60 Addis Ababa schools assessed WASH interventions among 6,229 children. Respiratory illness fell by 16%, but no effects were seen on diarrhoea or absence, suggesting limited impact of WASH programs on attendance and education.