Distribution of sociodemographic characteristics of the study population in all survey years, year before the partial ban (2013), years between the partial and comprehensive bans (2014–2015), and years after the comprehensive ban (2016–2017)
| All survey years | 2013 | 2014–2015 | 2016–2017 | |
| N observations | 6202 | 1357 | 2443 | 2402 |
| Gender | ||||
| Male | 51.1 | 51.7 | 51.4 | 50.4 |
| Female | 48.9 | 48.3 | 48.6 | 49.6 |
| Age (mean, SD), years | 14.5 (1.12) | 14.6 (1.12) | 14.5 (1.12) | 14.5 (1.12) |
| 12 | <0.1 | 0 | 0 | 0.1 |
| 13 | 20.9 | 20.5 | 21.1 | 20.8 |
| 14 | 31.8 | 30.2 | 31.4 | 33.1 |
| 15 | 18.7 | 19.0 | 19.0 | 18.2 |
| 16 | 28.2 | 30.0 | 28.0 | 27.3 |
| 17 | 0.4 | 0.3 | 0.5 | 0.5 |
| Ethnicity | ||||
| White | 94.6 | 94.5 | 94.8 | 94.3 |
| Non-white | 5.4 | 5.5 | 5.2 | 5.7 |
| School year | ||||
| Second year | 53.0 | 51.1 | 52.8 | 54.2 |
| Fourth year | 47.0 | 48.9 | 47.2 | 45.8 |
| Family Affluence Scale (FAS) | ||||
| Low | 32.7 | 33.1 | 33.0 | 32.3 |
| Intermediate | 32.7 | 32.6 | 32.4 | 33.0 |
| High | 34.6 | 34.3 | 34.6 | 34.8 |
| Smoking status | ||||
| Non-(current) smoker | 95.4 | 94.7 | 96.0 | 95.3 |
| Current smoker | 4.6 | 5.3 | 4.0 | 4.7 |
| E-cigarette use | ||||
| Never used | 59.9 | – | 84.6 | 68.5 |
| Used once or twice | 12.5 | – | 12.1 | 20.0 |
| Current/past occasional or regular use | 5.8 | – | 3.3 | 11.5 |
| 2013 (missing) | 21.9 | 100 | – | – |
| Family smoking | ||||
| Non-smoking family members | 61.2 | 56.0 | 60.1 | 65.3 |
| One smoking family member | 22.5 | 24.7 | 23.0 | 20.6 |
| At least two smoking family members | 16.3 | 19.3 | 16.8 | 14.1 |
| Friend smoking | ||||
| None of them | 54.1 | 55.1 | 60.3 | 47.3 |
| At least some of them | 34.2 | 34.3 | 28.0 | 40.5 |
| Don’t know | 11.6 | 10.5 | 11.7 | 12.2 |
| Visits to supermarkets | ||||
| Rarely | 21.4 | 20.0 | 21.4 | 22.3 |
| Sometimes | 57.0 | 56.4 | 56.2 | 58.1 |
| Often | 21.6 | 23.6 | 22.5 | 19.6 |
| Visits to small shops | ||||
| Rarely | 12.7 | 9.0 | 12.1 | 15.5 |
| Sometimes | 44.1 | 41.8 | 45.1 | 44.4 |
| Often | 43.2 | 49.2 | 42.8 | 40.1 |
Numbers represent percentages unless indicated otherwise.