Table 2

 Predictors of quitting by ITC-4 Wave 2 among baseline current smokers who made serious quit attempts between Waves 1 and 2

Entire sampleUSACanadaUKAustralia
n% quitORn% quitORn% quitORn% quitORn% quitOR
Statistically significant interactions exist between country and (1) heaviness of smoking index; (2) self-efficacy; and (3) favourable attitudes about smoking
p<0.05 for odds ratios that are underlined.
Outcome expectancy: Based on smokers’ responses to the question: “How much do you think you would benefit from health and other gains if you were to quit smoking permanently in the next 6 months?” Coded: 1: “not at all”, 2: “slightly”, 3: “moderately”, 4: “very much”, and 5: “extremely”.
Self-efficacy: Based on smokers’ responses to the question: “If you decided to give up smoking completely in the next 6 months, how sure are you that you would succeed?” Coded: 1: “not at all sure”, 2: “slightly sure”, 3: “moderately sure”, 4: “very sure”, and 5: “extremely sure”.
Worries about health and QOL: Based on smokers’ responses to the following two questions: (1) “How worried are you, if at all, that smoking will lower your quality of life in the future?” (2) “How worried are you, if at all, that smoking will damage your health in the future?” Both questions were coded: 1: not at all worried, 2: a little worried, 3: moderately worried, 4: very worried. Here we used the average for the two variables.
Favourable attitudes about smoking: Based on smokers’ responses to the following two questions: (1) “You enjoy smoking too much to give it up”; (2) Smoking is an important part of your life. Both questions were coded: 1: strongly disagree, 2: disagree, 3: neither agree or disagree, 4: agree, and 5: strongly agree. Here we used the average of the two variables.
Overall opinion of smoking: Based on smokers responses to the question of: “What is your overall opinion of smoking?”
Age at recruitment (years)
    55 and up43523%0.899820%0.7712119%0.9214230%0.977419%0.80
Highest level of education
    No response12227%1.392030%1.333921%1.173037%1.573324%1.52
Identified majority group
    White/English only197825%Ref33421%Ref61325%Ref50829%Ref52324%Ref
Intention to quit
    No intention23226%Ref4028%Ref5217%Ref8033%Ref6023%Ref
    Plan to quit beyond 6 months71623%1.0416818%0.5819924%1.6416226%1.0418725%1.50
    Plan to quit within 6 months81726%1.2114920%0.7328528%2.0218029%1.1320325%1.54
    Plan to quit within 1 month50924%1.089730%2.0115822%1.2710829%1.1814617%0.89
Tried to quit within last year
Longest time off smoking
    1 week or less33110%0.367010%0.301019%0.477613%0.46847%0.24
    Between 1 week and 6 months75620%0.7814616%0.6523323%1.1016720%0.7621018%0.66
    6 months or more93332%1.3319731%1.5728732%1.6821539%1.6323428%0.95
Heaviness of smoking index
Baseline smoking frequency
    Daily smoker199522%Ref39219%Ref62022%Ref47128%Ref51220%Ref
    Weekly/monthly smoker27941%1.416240%1.327449%2.005932%0.628439%1.81
Overall opinion of smoking
    Positive or neutral76624%Ref15425%Ref20825%Ref20625%Ref19823%Ref
    Very negative62523%1.2213017%0.6819925%0.8613329%1.9916321%1.60
Continuous variables
Outcome expectancy0.870.820.980.790.77
Worries about health and QOL0.900.860.980.721.06
Favourable attitudes about smoking1.051.270.781.121.32
Nagelkerke’s R20.