From: Respiratory symptoms in children living near busy roads and their relationship to vehicular traffic: results of an Italian multicenter study (SIDRIA 2)
Asthma symptoms
Cough or phlegm
YES
n (%)
NO
TOTAL
961 (2.9%)
1,337 (4.0%)
2,298 (6.8%)
3,591 (10.7%)
27,743 (82.5%)
31,334 (93.2%)
4,552 (13.5%)
29,080 (86.5%)
33,632 (100%)