Table 3.
Hierarchical Regression Results Predicting American Thoracic Society Questionnaire (ATSQ) Sum Score
| Predictor block | Model 1 | Model 2 | Model 3 | Model 4 | |
|---|---|---|---|---|---|
| Covariates | Age | −.00 | −.09 | −.00 | −.02 |
| Sex (1 = male, 2 = female) | .05 | .07 | .03 | .02 | |
| Race (0 = white, 1 = non-white) | .07 | .08 | .13 | .20* | |
| Cotinine level (ng/mL) | .10 | .12 | .07 | .01 | |
| Vaping topography variables | Number of puffs | −.25 | −.19 | −.11 | |
| Average puff time (s) | .04 | −.04 | −.09 | ||
| Interpuff interval (s) | −.08 | −.09 | .00 | ||
| Percent time spent vaping | .30 | .29 | .23 | ||
| E-cigarette use variables | Penn State Dependence Index Score | .15 | .11 | ||
| Number of mLs of e-liquid used in past 30 d | −.26* | −.16 | |||
| Labeled nicotine concentration | .09 | .02 | |||
| Combustible cigarette use | Any smoking in the past 30 d (0 = No, 1 = Yes) | .39** | |||
| R 2 | .02 | .06 | .14 | .26 | |
| R 2 change | .04 | .08 | .12 |
N = 110 for all models. Standardized coefficients (β) shown.
*Significant predictor, p < .05. **Significant predictor, p < .01.