Table 3. Cigarette use intensity and quit intentions according to past month use (yes or no) of electronic cigarettes, 2011–2015.
| Females, grades 6–12 | Males, grades 6–12 | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All past 30-day cigarette users (n: sample size) | Concurrent past 30-day e-cigarette use | 1 | All past 30-day cigarette users (n: sample size) | Concurrent past 30-day e-cigarette use | 1 | |||||||||
| Yes (n: sample size) | No (n: sample size) | Yes (n: sample size) | No (n: sample size) | |||||||||||
| Cigarettes all 30 days in past month: | ||||||||||||||
| n | % all 30 (SE) | n | % all 30 (SE) | n | % all 30 (SE) | n | % all 30 (SE) | n | % all 30 (SE) | n | % all 30 (SE) | |||
| All years | 3,633 | 20.2 (0.9) | 886 | 25.8 (2.2) | 2,749 | 18.4 (1.2) | 4,942 | 23.8 (0.9) | 1,458 | 29.2 (1.7) | 3,484 | 21.5 (1.1) | * | |
| 2011 | 893 | 21.2 (1.9) | -2 | - | 847 | 20.2 (2.0) | 1,165 | 26.3 (1.8) | 93 | 53.0 (7.2) | 1,072 | 23.2 (1.9) | * | |
| 2012 | 970 | 20.4 (1.8) | 145 | 32.5 (6.8) | 825 | 18.3 (2.0) | 1,349 | 23.7 (1.7) | 260 | 38.8 (4.9) | 1,089 | 20.2 (2.0) | * | |
| 2013 | 740 | 22.8 (2.3) | 143 | 35.0 (5.5) | 597 | 19.5 (2.9) | 894 | 25.1 (2.1) | 230 | 27.7 (4.6) | 664 | 24.2 (2.9) | ||
| 2014 | 577 | 20.2 (2.2) | 308 | 24.0 (3.3) | 269 | 16.0 (2.9) | 872 | 22.0 (2.2) | 470 | 26.0 (3.6) | 402 | 17.6 (3.2) | ||
| 2015 | 453 | 16.6 (2.2) | 244 | 41.0 (3.2) | 211 | 13.6 (2.9) | 662 | 21.4 (2.2) | 405 | 22.8 (2.8) | 257 | 19.2 (4.3) | ||
| Trend3 | 0.281 | 0.008 | 0.131 | 0.093 | <0.001 | 0.322 | ||||||||
| Smoked >10 cigarettes/day: | ||||||||||||||
| n | % 10/day (SE) | n | % 10/day (SE) | n | % 10/day (SE) | n | % 10/day (SE) | n | % 10/day (SE) | n | % 10/day (SE) | |||
| All years | 3,633 | 6.4 (0.5) | 886 | 9.9 (1.6) | 2,749 | 5.2 (0.6) | 4,942 | 12.4 (0.6) | 1,458 | 16.3 (1.5) | 3,484 | 10.8 (0.8) | ||
| 2011 | 893 | 6.1 (0.9) | -2 | - | 847 | 5.8 (0.9) | 1,165 | 13.4 (1.3) | 93 | 36.4 (7.7) | 1,072 | 10.8 (1.2) | ||
| 2012 | 970 | 6.5 (1.1) | 145 | 9.5 (4.0) | 825 | 6.0 (1.2) | 1,349 | 13.8 (1.3) | 260 | 20.1 (3.7) | 1,089 | 12.5 (1.5) | ||
| 2013 | 740 | 8.2 (1.3) | 143 | 16.8 (5.8) | 597 | 6.1 (1.9) | 894 | 13.9 (1.4) | 230 | 17.5 (4.0) | 664 | 12.5 (1.9) | ||
| 2014 | 577 | 7.9 (1.3) | 308 | 10.6 (2.1) | 269 | 4.6 (1.6) | 872 | 10.9 (2.0) | 470 | 13.7 (3.4) | 402 | 7.7 (2.9) | ||
| 2015 | 453 | 4.7 (1.1) | 244 | 6.7 (2.1) | 211 | 2.5 (1.3) | 662 | 10.0 (1.0) | 405 | 11.2 (2.0) | 257 | 8.4 (2.2) | ||
| Trend3 | 0.761 | 0.212 | 0.258 | 0.047 | <0.001 | 0.274 | ||||||||
| Cigarette quit attempt in past year: | ||||||||||||||
| n | % quit attempt (SE) | n | % quit attempt (SE) | n | % quit attempt (SE) | n | % quit attempt (SE) | n | % quit attempt (SE) | n | % quit attempt (SE) | |||
| All years | 3,633 | 61.1 (1.2) | 886 | 64.1 (2.9) | 2,749 | 60.1 (1.5) | 4,942 | 58.1 (1.0) | 1,458 | 57.4 (2.0) | 3,484 | 58.4 (1.3) | ||
| 2011 | 893 | 59.5 (2.4) | -2 | - | 847 | 60.0 (2.6) | 1,165 | 57.7 (2.3) | 93 | 57.4 (6.9) | 1,072 | 57.7 (2.4) | ||
| 2012 | 970 | 61.7 (2.3) | 145 | 60.6 (6.3) | 825 | 61.9 (2.3) | 1,349 | 55.7 (2.0) | 260 | 51.5 (5.8) | 1,089 | 56.7 (2.4) | ||
| 2013 | 740 | 57.8 (2.6) | 143 | 56.4 (6.2) | 597 | 58.1 (3.0) | 894 | 58.8 (2.2) | 230 | 56.0 (4.4) | 664 | 60.3 (2.8) | ||
| 2014 | 577 | 61.6 (2.8) | 308 | 62.1 (3.9) | 269 | 60.4 (4.6) | 872 | 61.4 (2.7) | 470 | 58.2 (3.7) | 402 | 64.4 (4.5) | ||
| 2015 | 453 | 66.6 (3.5) | 244 | 73.1 (4.3) | 211 | 57.7 (5.5) | 662 | 58.0 (3.1) | 405 | 58.8 (4.3) | 257 | 55.2 (5.1) | ||
| Trend3 | 0.194 | 0.023 | 0.618 | 0.370 | 0.509 | 0.500 | ||||||||
| Thinking about quitting cigarettes: | ||||||||||||||
| n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | |||
| All years | 3,633 | 58.6 (1.4) | 886 | 59.6 (2.5) | 2,749 | 58.2 (1.7) | 4,942 | 58.4 (1.1) | 1,458 | 59.0 (2.0) | 3,484 | 58.1 (1.4) | ||
| 2011 | 893 | 52.7 (3.2) | -2 | - | 847 | 52.9 (3.3) | 1,165 | 47.8 (2.5) | 93 | 48.7 (9.0) | 1,072 | 47.8 (2.7) | ||
| 2012 | 970 | 64.6 (2.0) | 145 | 62.6 (5.9) | 825 | 65.1 (2.1) | 1,349 | 64.7 (1.8) | 260 | 55.4 (5.1) | 1,089 | 67.6 (2.2) | ||
| 2013 | 740 | 55.0 (3.2) | 143 | 49.4 (6.8) | 597 | 56.4 (3.7) | 894 | 57.8 (2.6) | 230 | 56.6 (5.3) | 664 | 58.4 (3.1) | ||
| 2014 | 577 | 61.7 (2.6) | 308 | 61.1 (3.7) | 269 | 61.9 (3.8) | 872 | 63.3 (2.6) | 470 | 60.6 (3.5) | 402 | 65.6 (4.8) | ||
| 2015 | 453 | 61.8 (3.4) | 244 | 63.0 (4.6) | 211 | 60.3 (4.4) | 662 | 61.5 (3.3) | 405 | 62.4 (3.6) | 257 | 59.7 (5.4) | ||
| Trend3 | 0.129 | 0.372 | 0.233 | 0.003 | 0.111 | 0.009 | ||||||||
| Thinking about quitting all tobacco: | ||||||||||||||
| n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | n | % think quit (SE) | |||
| All years | 3,633 | 53.9 (1.3) | 886 | 48.3 (2.6) | 2,749 | 56.0 (1.6) | 4,942 | 48.2 (1.1) | 1,458 | 45.4 (2.1) | 3,484 | 49.5 (1.3) | ||
| 2011 | 893 | 54.7 (2.9) | -2 | - | 847 | 54.7 (2.9) | 1,165 | 46.3 (1.9) | 93 | 49.5 (7.2) | 1,072 | 46.1 (2.1) | ||
| 2012 | 970 | 60.2 (2.5) | 145 | 54.5 (6.6) | 825 | 61.1 (2.6) | 1,349 | 54.3 (2.0) | 260 | 50.5 (5.3) | 1,089 | 55.5 (2.4) | ||
| 2013 | 740 | 52.1 (3.0) | 143 | 47.9 (6.3) | 597 | 53.5 (3.7) | 894 | 50.6 (2.9) | 230 | 49.0 (5.3) | 664 | 51.5 (3.2) | ||
| 2014 | 577 | 44.4 (2.8) | 308 | 40.7 (4.3) | 269 | 49.7 (4.7) | 872 | 43.9 (3.0) | 470 | 41.9 (3.5) | 402 | 46.1 (4.9) | ||
| 2015 | 453 | 55.0 (3.9) | 244 | 52.3 (4.1) | 211 | 57.8 (5.4) | 662 | 43.3 (3.1) | 405 | 42.3 (4.1) | 257 | 44.6 (4.5) | ||
| Trend3 | 0.155 | 0.476 | 0.766 | 0.135 | 0.101 | 0.943 | ||||||||
Among past 30-day cigarette users, past 30-day e-cigarette use was not associated with cigarette quit attempts or quit intentions.
1. Chi-square test for difference in cigarette smoking intensity or quit behavior/intentions between past 30-day cigarette users with or without past 30-day e-cigarette use (* P < 0.001)
2. Estimates suppressed due to sample size (n < 50)
3. P-for-linear trend, 2011–2015
Marginal percentages adjusted across years for grade in school and race/ethnicity
Subgroup sample sizes (n) are the mean sample size over 10 imputations for missing value assignment.
Abbreviations: n = sample size (denominator); SE = standard error