2022 Yes https://www.sciencedirect.com/science/article/pii/S0048969722039213?via%3Dihub Zhang, Ting Asia Epidemiology Study Students Elementary (K-5) Particulate Matter (PM) Ozone (O3) Nitrogen Dioxide (NO2) Sulfur dioxide (SO2) Absenteeism Fine particulate matter Ozone Children's health Illness-related school absenteeism Hospital visit record An increase of 10 ?g/m3 in the current-day concentration of PM2.5 and O3 was positively associated with illness-related absenteeism overall. The excess risk of absenteeism was 4.52 % (95%CI 4.37-4.67 %) for PM2.5 and 0.25 % (95%CI 0.01-0.36 %) for O3. The risk associated with O3 was boosted for the frequent absentees who tended to have basic diseases or were more vulnerable to infectious diseases. Students in 43.1 % illness-related absenteeism, mainly due to highly infectious diseases, only received home nursing without going to a hospital. The increase in the number of illness cases associated with PM2.5 and O3 estimated based on the illness-related absence data was 41.5 % and 18.6 % higher than that evaluated based on hospital visit records. Such underestimations persisted in sensitivity analyses and persisted in subgroups classified by gender or grade. Together, the performance of illness-related absence records far outweighed that of hospital visit data regarding the thorough evaluation of air pollution-related illness cases for elementary students. Improvement in air quality and home health care education are warranted as well for the health benefits of children.