There is probable correlation between home distance from highways and rates of childhood asthma (though my mental guess is that may be confounded by mostly poor

There is probable correlation between home distance from highways and rates of childhood asthma (though my mental guess is that may be confounded by mostly poorer people living close to the highway or having a high traffic road built next to them). I just picked one article for reference. Of course both methods could be responsible in some way. https://www.scientificamerican.com/article/traffic-pollution-and-asthma/ https://www.scientificamerican.com/article/traffic-pollution...