Table 1 Demographic information and smoking measures.

Age (years)

53.09 ± 4.96 (45–64)

54.64 ± 6.48 (42–69)

56.30 ± 7.12 (42–66)

F(2, 78) = 1.76

P = 0.18

Education^a

3.67 ± 1.14

3.32 ± 1.12

3.00 ± 0.97

χ²(8) = 14.37

P = 0.073

Income level^b

3.15 ± 1.25

3.14 ± 1.41

2.85 ± 1.42

F(2, 78) = 0.37

P = 0.69

K-BDI-II

8.63 ± 6.89

(1–27)

9.96 ± 6.50

(2–29)

8.75 ± 6.27

(0–22)

F(2, 78) = 0.35

P = 0.71

Age of smoking initiation**

–

19.43 ± 1.32

(17–22)

18.10 ± 1.80

(15–22)

t(46) = –2.95

P = 0.0049

Years smoking***

–

10.21 ± 6.43

(0.5–20)

37.80 ± 7.54

(23–50)

t(46) = 13.63

P = 9.07e−18

Cigarettes per day^c

–

18.24 ± 9.05

(10–40)

20.53 ± 6.76

(9–30)

t(38) = − 0.90

P = 0.38

Quit attempts^c

–

2.11 ± 2.11

(1–10)

2.15 ± 1.04

(1–5)

U = 142.00

P = 0.12

Abstinence duration

–

24.84 ± 4.70 years

(20–36)

4.80 ± 6.28 days

(2–30)

–

FTND total**^,c

–

3.15 ± 3.17

(0–10)

5.58 ± 2.09

(3–10)

t(37) = 2.81

P = 0.0079

QSU-brief***^,c

–

10.80 ± 2.73

(10–22)

21.32 ± 10.17

(10–43)

t(37) = 4.46

P = 7.30e−05