2021 Yes https://doi.org/10.1016/j.buildenv.2021.108565 Young, Bonnie North America Epidemiology Study Modeling Students Elementary (K-5) Carbon Dioxide (CO2) Particulate Matter (PM) Volatile Organic Compounds (VOCs) Absenteeism Absenteeism Elementary schools Indoor air quality Carbon dioxide (CO2) Particulate matter (PM) Simulation Used absenteeism data and pollutant models in elementary schools to simulate IAQ improvements. CO₂ reduction showed strongest link to lower absences. Results support ventilation investment to improve equity in school attendance.