2020 No https://doi.org/10.1111/ina.12706 Du, Bowen Review Students Teachers Other Elementary (K-5) Middle/Jr High (6-8) High School (9-12) Carbon Dioxide (CO2) Cognitive function Review synthesized findings from 37 studies on indoor CO₂ exposure and cognitive performance, highlighting methodological gaps; calls for policy-guided research to establish safe exposure limits in schools.