Table 2.
Results of bivariate logistic regression models predicting past month electronic cigarette use and ever use of electronic cigarettes to quit smoking in three study samples.
| Study 1: 2009–2010 (n = 1987) | Study 2: 2010–2011 (n = 595) | Study 3: 2013 (n=79) | ||||
|---|---|---|---|---|---|---|
| Past Month EC Usea | Ever EC Use to Quitb | Past Month EC Usea | Ever EC Use to Quitb | Past Month EC Usea | Ever EC Use to Quitb | |
| OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | |
| Demographics | ||||||
| Age | 0.98 (0.90, 1.07) | 1.17 (0.97, 1.41) | 0.88 (0.78, 0.99) | 0.95 (0.71, 1.27) | 0.89 (0.72, 1.10) | 0.94 (0.76, 1.17) |
| Male (vs. Female) | 2.07 (1.34, 3.18) | 0.76 (0.33, 1.74) | 1.79 (1.09, 2.95) | 3.01 (0.68, 13.4) | 1.17 (0.38, 3.62) | 1.03 (0.33, 3.18) |
| White (vs. Non-white) | 1.17 (0.78, 1.78) | 0.92 (0.38, 2.26) | 0.84 (0.54, 1.29) | 1.40 (0.45, 4.39) | 0.62 (0.20, 1.86) | 0.74 (0.24, 2.25) |
| Years of education | 1.06 (0.98, 1.14) | 1.16 (1.02, 1.33) | 0.99 (0.87, 1.14) | 1.23 (0.90, 1.68) | 1.19 (0.92, 1.54) | 0.94 (0.74, 1.18) |
| Household income (Ref: <$20,000) | ||||||
| $20,000–$60,000 | 0.90 (0.56, 1.44) | 0.87 (0.29, 2.60) | 1.12 (0.66, 1.88) | 1.33 (0.38, 4.62) | 1.47 (0.49, 4.40) | 0.46 (0.15, 1.38) |
| $60,000–$100,000 | 1.41 (0.85, 2.33) | 1.42 (0.46, 4.44) | 1.24 (0.69, 2.24) | 1.34 (0.33, 5.46) | 1.53 (0.40, 5.82) | 0.67 (0.18, 2.52) |
| >$100,000 | 0.90 (0.50, 1.61) | 1.05 (0.29, 3.74) | 1.03 (0.51, 2.04) | 0.49 (0.05, 4.43) | 0.29 (0.03, 2.88) | 0.40 (0.06, 2.52) |
| Region (Ref: West) | ||||||
| South | 0.67 (0.40, 1.10) | 1.01 (0.32, 3.15) | 0.61 (0.34, 1.07) | 0.85 (0.25, 2.84) | 1.22 (0.33, 4.57) | 1.93 (0.50, 7.49) |
| Midwest | 0.97 (0.61, 1.55) | 1.08 (0.35, 3.38) | 0.70 (0.40, 1.22) | 0.51 (0.12, 2.06) | 0.69 (0.22, 2.20) | 1.08 (0.32, 3.63) |
| Northeast | 0.73 (0.42, 1.25) | 1.18 (0.36, 3.88) | 0.86 (0.48, 1.54) | 0.45 (0.09, 2.26) | 1.38 (0.30, 6.40) | 2.17 (0.45, 10.4) |
| Cigarette Variables | ||||||
| Cigarettes per day | 1.02 (1.00, 1.05) | 1.02 (0.97, 1.07) | 1.02 (0.99, 1.04) | 1.05 (0.99, 1.10) | 1.01 (0.96, 1.07) | 0.99 (0.94, 1.05) |
| Daily smoker | 1.85 (1.19, 2.88) | 2.27 (0.77, 6.70) | 1.62 (0.99, 2.65) | 1.79 (0.50, 6.35) | 1.84 (0.62, 5.44) | 1.19 (0.41, 3.42) |
| Smoke within 30 mins of waking | 1.63 (1.13, 2.35) | 2.74 (1.18, 6.37) | 1.33 (0.88, 2.01) | 1.36 (0.50, 3.68) | 1.09 (0.44, 2.67) | 1.10 (0.44, 2.73) |
| Hard to not smoke where banned | 1.40 (0.93, 2.16) | 1.01 (0.37, 2.73) | 1.52 (0.97, 2.40) | 1.88 (0.67, 5.26) | 1.75 (0.66, 4.62) | 0.57 (0.20, 1.61) |
| Identify as “social smoker” | 0.91 (0.61, 1.37) | 0.86 (0.34, 2.18) | 0.77 (0.50, 1.17) | 0.53 (0.20, 1.44) | 2.02 (0.72, 5.66) | 1.03 (0.38, 2.77) |
| Total years smoking | 1.01 (0.95, 1.07) | 1.07 (0.95, 1.21) | 0.98 (0.91, 1.06) | 1.00 (0.84, 1.20) | 1.09 (0.55, 2.17) | 1.01 (0.51, 2.02) |
| Past year quit attempt | 1.54 (1.03, 2.30) | 4.15 (1.23, 14.0) | 1.26 (0.83, 1.91) | 5.67 (1.28, 25.1) | 0.62 (0.25, 1.54) | 3.11 (1.16, 8.32) |
| Desire to stop smoking | 1.00 (0.94, 1.07) | 1.10 (0.96, 1.26) | N/A | N/A | 0.99 (0.84, 1.16) | 1.29 (1.08, 1.55) |
| Expected success for quitting | 0.93 (0.87, 0.99) | 1.00 (0.87, 1.16) | N/A | N/A | 1.05 (0.89, 1.23) | 1.02 (0.87, 1.21) |
| Expected difficulty for quitting | 1.08 (1.01, 1.16) | 1.24 (1.03, 1.48) | N/A | N/A | 1.11 (0.92, 1.35) | 1.10 (0.91, 1.34) |
| Smoking goal of abstinence | 0.58 (0.28, 1.20) | 1.30 (0.38, 4.39) | N/A | N/A | 0.18 (0.02, 1.58) | 1.73 (0.40, 7.51) |
| Smoking stage of change (Ref: Preceontemplation) | ||||||
| Contemplation | 0.85 (0.55, 1.32) | 2.02 (0.75, 5.45) | 1.09 (0.68, 1.75) | 0.89 (0.23, 3.48) | 0.53 (0.20, 1.41) | 1.46 (0.54, 3.98) |
| Preparation | 1.10 (0.70, 1.73) | 2.14 (0.75, 6.14) | 1.25 (0.69, 2.24) | 3.71 (1.22, 11.36) | 0.71 (0.17, 2.98) | 3.45 (0.80, 15.0) |
Notes: Ref = Reference group.
a
Past-month electronic cigarette use.
b
Ever use e-cigarette during a quit attempt. Use of e-cigarettes during a cessation attempt was reported spontaneously in first two studies, and prompted in third study. Significant values shown in bold.