Table 1 Participant characteristics

 Age

33.9 ± 1.7

32.4 ± 2.3

35.9 ± 2.5

0.31

 African American (n), %

50.0 (19)

50.0 (11)

50.0 (8)

1.00

 Years of education

14.4 ± 0.3

14.4 ± 1.8

14.5 ± 2.6

0.90

 Cigarettes per day

12.6 ± 0.7

11.5 ± 0.9

13.9 ± 1.1

0.12

 Years smoking

14.6 ± 1.8

12.7 ± 2.4

17.3 ± 2.5

0.21

 Pack years^a

10.3 ± 1.5

8.6 ± 2.0

12.7 ± 2.3

0.20

 FTND scores

4.4 ± 0.3

4.1 ± 0.3

4.9 ± 0.4

0.13