2017 No http://dx.doi.org/10.1016/j.envint.2017.07.010 Wu, Jianyong North America Epidemiology Study Students Elementary (K-5) Green space Other Autism spectrum disorder (ASD) Greenness Near-road tree canopy Air pollution School children District-level study in California linked autism prevalence to various green space metrics; found tree canopy and grassland near roads inversely associated with autism rates.