학교 실내 간접 흡연 일수도 1일 단위로 증가할 때마다 전자 담배를 사용할 확률이 1.10배 증가하는 것으로 나타났다.
It was found that the probability of using e-cigarettes increased by 1.10 times each time the number of days of secondhand smoke indoors at school increased by 1 day.