Table 2.

Odds ratios for regular use of e-cigarettes among pupils in Wales between 2015 and 2017, overall and by gender, school year, and smoking status (before and after analyses)

			P
All (n=47,318)	Time	1.07 [0.98, 1.17]	0.118
Boys (n=23,095)	Time	1.11 [1.00, 1.24]	0.056
Girls (n=24,233)	Time	1.02 [0.91, 1.14]	0.770
Year 9 (n=26,390)	Time	1.14 [1.00, 1.28]	0.043
Year 11 (n=20,928)	Time	1.03 [0.93, 1.14]	0.571
Never smoker (n=38,014)	Time	1.14 [0.98, 1.31]	0.083
Ever smoker (n=7,920)	Time	1.03 [0.94, 1.12]	0.527

Note: where appropriate, models adjusted for gender and/or school year