Table 1. Baseline characteristics of the subjects.

Characteristic	Intervention	Control	p value
Mean age ± SD (year)	56.4±12.8	53.2±10.5	0.03
Male (%)	95.3	91.5	0.27
Higher education (%)*	7.0	9.3	0.47
Married status (%)	75.6	72.4	0.62
Self-reported health (%)
Excellent	28.4	30.2	0.38
Fair	60.3	52.1
Poor	11.3	16.7
Three most frequently engaged occupations for the longest time
Factory workers	35.1	31.4	0.42
Commercial and service personnel	15.0	12.9
Officer	10.2	12.8
Mean age at smoking initiation (year)	24.8±9.2	24.6±8.6	0.84
Mean duration of smoking ± SD (year)	31.6±14.1	28.3±10.3	0.04
Mean daily cigarette consumption ± SD (n)	15.4±11.4	14.9±7.5	0.71
The number of previous quit attempt	1.3±1.1	1.1±1.2	0.11
Extent of addiction (%)
Low to middle	71.5	81.3	0.09
High	28.5	18.7
Stage of change (%)
Pre-contemplation	36.2	42.7	0.62
Contemplation	44.8	42.7
Preparation	18.0	14.6
Agree that smoking has done harm to health (%)	23.7	20.6	0.34
Self-belief in quitting ability	5.1±1.7	4.3±1.6	0.01

*: university degree or higher

SD: standard deviation