Time point | Analysis population | Quit smoking/total | Univariable OR (95% CI) | Multivariable OR‡ (95% CI) | |
CT scan (n=759) | Control (n=787) | ||||
T1 (2 weeks) | Primary ITT* complete case | 75/758 (10%)† 75/527 (14%) | 36/786 (5%)† 36/479 (8%) | 2.29 (1.52 to 3.45) 2.04 (1.34 to 3.10) | 2.38 (1.56 to 3.64) 2.09 (1.36 to 3.23) |
T2 (2 years) | Primary ITT* complete case | 115/749 (15%)† 115/488 (24%) | 79/775 (10%)† 79/377 (21%) | 1.60 (1.18 to 2.17) 1.16 (0.84 to 1.61) | 1.60 (1.17 to 2.18) 1.16 (0.65 to 1.33) |
*Primary intention to treat (ITT) analysis using the imputed population. Where no data were available on smoking status at follow-up, the participant was assumed to be smoking.
†Participants were excluded due to administrative error: T1 CT scan (n=1); T1 control (n=1); T2 CT scan (n=10); T2 control (n=12).
‡Adjusted for T0 cancer distress, recruitment site, gender, age, marital group, deprivation and experience of lung cancer.