Table 2.
Characteristics Among Baseline Exclusive E-Cigarette Users/Follow-Up Exclusive E-Cigarette Users, Baseline Exclusive E-Cigarette Users/Follow-Up Poly Users,a and Baseline Poly Usersa/Follow-Up Exclusive E-Cigarette Users
| Characteristics | Baseline exclusive e-cigarette users/follow-up exclusive e-cigarette users (n=355) |
Baseline exclusive e-cigarette users/follow-up poly users (n=37) |
Baseline poly users/follow-up exclusive e-cigarette users (n=43) |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Follow-up | p-valueb | Baseline | Follow-up | p-valueb | Baseline | Follow-up | p-valueb | |
| Age (years), mean (SD) | 41.3 (11.9) | 45.0 (11.9) | — | 36.8 (11.4) | 40.6 (11.5) | — | 40.6 (11.5) | 44.3 (11.5) | — |
| College or higher, n (%) | 165 (46.5) | 167 (47.0) | 0.75 | 16 (43.2) | 20 (54.1) | 0.05 | 20 (46.5) | 22 (51.2) | 0.16 |
| Full-time employed, n (%) | 251 (70.7) | 241 (67.9) | 0.21 | 21 (56.8) | 24 (64.9) | 0.37 | 29 (67.4) | 28 (65.1) | 0.71 |
| Intended to quit smoking when starting e-cigarette use, n (%) | 263 (74.3) | 254 (71.8) | 0.25 | 24 (64.9) | 23 (62.2) | 0.76 | 33 (76.7) | 33 (76.7) | 1.00 |
| Mean number of devices used before the current device (SD) | 5.0 (6.0) | 11.0 (13.3) | 0.002 | 3.5 (4.9) | 9.9 (15.4) | 0.01 | 2.6 (2.6) | 8.9 (10.2) | <0.0001 |
| Mean e-cigarette use times per day (SD) | 24.5 (24.8) | 21.4 (22.9) | 0.03 | 15.7 (12.6) | 16.6 (24.1) | 0.84 | 21.7 (26.4) | 25.2 (27.3) | 0.50 |
| Daily e-cigarette use in the past 28 days or 30 days, n (%) | 338 (95.2) | 333 (93.8) | 0.51 | 29 (78.4) | 29 (78.4) | 1.0 | 24 (55.8) | 41 (95.3) | 0.0001 |
| Using a “ciglike” e-cigarette, n (%) | 35 (9.9) | 13 (3.7) | <0.0001 | 7 (18.9) | 6 (16.2) | 0.71 | 14 (32.6) | 7 (16.3) | 0.02 |
| Using an e-cigarette with a button that you can press before puffing, n (%) | 313 (88.7) | 337 (95.5) | <0.0001 | 30 (81.1) | 32 (86.5) | 0.32 | 28 (65.1) | 36 (83.7) | 0.01 |
| Using an e-cigarette that allows you to control the battery voltage, n (%) | 220 (62.2) | 258 (72.9) | 0.0008 | 22 (59.5) | 27 (73.0) | 0.13 | 17 (39.5) | 31 (72.1) | 0.001 |
| Using a “mod” e-cigarette, n (%) | 215 (60.6) | 244 (68.7) | 0.007 | 21 (56.8) | 23 (62.2) | 0.53 | 15 (34.9) | 22 (51.2) | 0.07 |
| Mean PSECDI (SD) | 8.6 (3.4) | 8.3 (3.8) | 0.25 | 7.4 (3.1) | 8.0 (3.4) | 0.39 | 8.3 (3.6) | 8.5 (3.7) | 0.82 |
Note: Boldface indicates statistical significance (p<0.05).
a
E-cigarette and other tobacco products.
b
Paired t-test or McNemar’s test p-values were used to examine changes in characteristics between baseline and follow-up.
PSECDI, Penn State Electronic Cigarette Dependence Index.