TABLE 1

Participant Characteristics at Baseline and Association of Each Characteristic With Number of Cigarettes Smoked in the Past 30 Days at Follow-up (N = 1312)

N (%)aMean No. Cigarettes Smoked at Follow-up (SE)RR (95% CI)b
Sex
 Female685 (52.2)5.40 (3.13)Reference
 Male627 (47.8)7.11 (1.71)1.51 (1.07–2.11)
Race and/or ethnicity
 Hispanic white635 (48.4)3.79 (1.27)Reference
 Non-Hispanic white506 (38.6)6.94 (1.94)0.96 (0.67–1.37)
 African American51 (3.9)2.04 (1.31)1.41 (0.55–3.58)
 Asian American13 (1.0)0 (0)
 Other107 (8.2)19.9 (19.0)1.06 (0.57–1.95)
Highest parental education
 ≤12th grade391 (29.8)1.95 (0.74)Reference
 Some college459 (35.0)8.24 (2.48)2.33 (1.46–3.72)
 College degree or higher386 (29.4)3.70 (1.24)2.21 (1.34–3.63)
E-cigarette use
 Never828 (63.1)1.86 (0.88)Reference
 Previous346 (26.4)13.0 (6.34)1.69 (1.02–2.79)
 Past 30 d138 (10.5)15.4 (4.39)2.67 (1.52–4.69)
Cigarette use
 Never978 (74.5)0.57 (0.35)Reference
 Previous221 (16.8)3.48 (1.28)4.17 (2.45–7.10)
 Past 30 d113 (8.61)60.4 (20.2)6.40 (3.07–13.3)
  • —, unable to be calculated.

  • a May not sum to total because of missing values.

  • b Coadjusted for sex, race and/or ethnicity, parental education, log-transformed number of cigarettes at baseline, e-cigarette use at follow-up, and number of days of e-cigarette use in the past 30 d at baseline by using Poisson regression models.