Table 3.

Relative odds of having attempted to quit smoking and of having received support during quit attempts, by country (2002–2005)

Country	Wave 2	Wave 3	Wave 4	Waves 2–4 combined
	Adjusted odds ratio (95% CI)
Made one or more attempts to quit
The United Kingdom	Referent
Australia	1.22 (1.04–1.66)	1.45 (1.22–1.58)	1.08 (0.91–1.28)	1.25 (1.12–1.40)
Canada	1.86 (1.59–2.17)	1.60 (1.35–1.90)	1.04 (0.87–1.23)	1.50 (1.34–1.67)
The United States	1.40 (1.18–1.66)	1.31 (1.09–1.58)	1.02 (0.86–1.22)	1.25 (1.11–1.40)
Among whom
Received support from specialist stop smoking clinic or helpline
The United Kingdom	Referent
Australia	0.45 (0.31–0.68)	0.42 (0.28–0.62)	0.22 (0.15–0.33)	0.34 (0.27–0.44)
Canada	0.42 (0.28–0.63)	0.44 (0.30–0.64)	0.38 (0.27–0.55)	0.40 (0.32–0.51)
The United States	0.83 (0.57–1.22)	0.61 (0.41–0.91)	0.42 (0.29–0.60)	0.59 (0.47–0.74)
Received pharmacotherapy
The United Kingdom	Referent
Australia	0.92 (0.69–1.23)	0.78 (0.58–1.04)	0.60 (0.45–0.80)	0.76 (0.64–0.92)
Canada	0.91 (0.69–1.20)	0.74 (0.22–0.98)	0.51 (0.38–0.68)	0.70 (0.58–0.84)
The United States	0.57 (0.42–0.79)	0.53 (0.38–0.73)	0.59 (0.44–0.80)	0.56 (0.46–0.68)
Received additional help or referral from a doctor or other health professional
The United Kingdom	Referent
Australia	0.26 (0.15–0.42)	0.40 (0.26–0.61)	0.32 (0.20–0.49)	0.32 (0.24–0.42)
Canada	0.40 (0.26–0.61)	0.33 (0.22–0.51)	0.43 (0.28–0.65)	0.38 (0.29–0.49)
The United States	0.45 (0.28–0.71)	0.51 (0.33–0.78)	0.53 (0.35–0.80)	0.48 (0.37–0.63)
Received both pharmacotherapy and help from a clinic, helpline, doctor, or health professional
The United Kingdom	Referent
Australia	0.38 (0.24–0.62)	0.37 (0.24–0.56)	0.23 (0.15–0.36)	0.33 (0.25–0.43)
Canada	0.37 (0.23–0.58)	0.37 (0.24–0.54)	0.33 (0.22–0.49)	0.35 (0.27–0.45)
The United States	0.45 (0.28–0.74)	0.39 (0.25–0.61)	0.42 (0.28–0.64)	0.42 (0.32–0.55)