eTable 3. Sample size and 30-day prevalence [95% confidence interval] of the use of conventional tobacco products and alternative products (from 2015) by survey year and gender; age 18–24 years.
| Conventional tobacco | E-cigarette | Waterpipe | Heat-not-burn product | |||||||
| Survey year | ncc | % | 95% CI | % | 95% CI | % | 95% CI | % | 95% CI | |
| Women | 1995 | 400 | 33.1 | [28.0; 38.7] | – | – | – | – | – | – |
| 1997 | 450 | 36.4 | [30.9; 42.2] | – | – | – | – | – | – | |
| 2000 | 554 | 39.6 | [35.5; 43.8] | – | – | – | – | – | – | |
| 2003 | 1066 | 39.7 | [37.0; 42.5] | – | – | – | – | – | – | |
| 2006 | 1014 | 37.8 | [34.9; 40.8] | – | – | – | – | – | – | |
| 2009 | 1133 | 30.1 | [27.3; 33.0] | – | – | – | – | – | – | |
| 2012 | 1149 | 23.5 | [21.0; 26.2] | – | – | – | – | – | – | |
| 2015 | 1225 | 19.4 | [17.4; 21.5] | 1.8 | [1.2; 2.7] | – | – | – | – | |
| 2018 | 1133 | 17.3 | [15.2; 19.6] | 4.0 | [3.0; 5.4] | 13.5 | [11.5; 15.8] | 0.6 | [0.3; 1.3] | |
| 2021 | 1156 | 15.5 | [13.4; 17.9] | 5.3 | [4.2; 6.8] | 14.7 | [12.5; 17.2] | 1.2 | [0.7; 2.1] | |
| Men | 1995 | 390 | 50.2 | [44.5; 55.9] | – | – | – | – | – | – |
| 1997 | 449 | 45.4 | [39.9; 50.9] | – | – | – | – | – | – | |
| 2000 | 409 | 45.4 | [40.9; 50.1] | – | – | – | – | – | – | |
| 2003 | 808 | 42.0 | [38.4; 45.8] | – | – | – | – | – | – | |
| 2006 | 864 | 41.5 | [37.8; 45.3] | – | – | – | – | – | – | |
| 2009 | 919 | 37.4 | [34.4; 40.5] | – | – | – | – | – | – | |
| 2012 | 985 | 29.8 | [26.9; 32.9] | – | – | – | – | – | – | |
| 2015 | 1145 | 28.4 | [25.8; 31.2] | 3.0 | [2.2; 4.1] | – | – | – | – | |
| 2018 | 971 | 23.6 | [21.2; 26.2] | 8.0 | [6.4; 9.9] | 22.4 | [19.6; 25.4] | 4.1 | [2.8; 5.8] | |
| 2021 | 932 | 22.0 | [19.0; 25.3] | 7.3 | [5.7; 9.5] | 18.4 | [15.6; 21.5] | 1.6 | [0.9; 2.6] | |
ncc, Unweighted sample size with complete information for all variables; CI, confidence interval