Table 2.

Average cigarettes per day during the three diary phases and 3 weeks and 6 months continuous abstinence rates for the intervention group and control group (N=162).

Variables	Intervention group (n=81)	Control group (n=81)	Intervention group vs control groupa	P value
CPDb baseline diary (N=162), mean (SD)	12.41 (7.50)	11.48 (7.08)	−0.81 (160)c	.42
CPD challenge diary prequit (n=149), mean (SD)	12.31 (7.29)	10.48 (6.15)	−1.67 (147)c	.10
CPD challenge diary postquit (n=144), mean (SD)	1.99 (4.03)	2.51 (3.14)	0.86 (142)c	.39
CPD follow-up diary (n=108), mean (SD)	6.13 (8.17)	4.99 (5.74)	−0.84 (91)c	.40
3 weeks continuous abstinence (ITTd) (N=162), n (%)	25 (30.9)	19 (23.5)	1.1 (1)e	.19
6 months continuous abstinencef (ITT) (N=162), n (%)	18 (22.2)	11 (13.6)	2.1 (1)e	.11

^aGroups were compared for number of cigarettes per day and continuous abstinence rates using independent t tests for continuous data and chi-square tests for categorical data.

^bCPD: cigarettes per day; the available data for the variable cigarettes per day varied due to dropout.

^ct test (df) values.

^dITT: intention to treat; lost participants were treated as smoking (full sample).

^eChi-square (df) values.

^fSix months continuous abstinence is defined as ≤5 cigarettes since quit date and no smoking during the follow-up diary phase (carbon monoxide verified).