METHOD
Participants
A total of 3530 smokers and recent quitters (quit within the last 2weeks)were recruited between November 2008 and November 2009. Recent quitters were included because the interventions have a relapse prevention component. Power (80% for P < 0.05) was based on a base rate of 12% cessation for the controls, 18% for both single interventions and 23% for the combined interventions (based on effective use of the interventions of approximately 70%), requiring 405 in the control group and 810 in each of the intervention groups (total = 3645), numbers we just failed to achieve. There were two main sources of recruitment: (i) information-seekers (n = 1335), mainly callers to the Victorian or South Australian Quitlines who were not seeking assistance from a counsellor; 1139 of 2643 by telephone (21.4% were ineligible, 15.2% refused and 16.1% were not contacted) and 196 via the study website due to either a recruitment e-mail to the above sample or via a link on the Quit Victoria website; and (ii) a cold-contacted sample (n = 2195), taken from two internet survey panels maintained by iView, a Melbourne-based market and social research company: the first 952 (10.9%) from 8766 previously identified smokers at some recent time and 1315 (1.9%) of 70 884 people of unknown smoking status; all enrolled on the study website. Females were over-represented (60%), mean age 42.1 years (range 18–80); 87.4% were currently smoking,and participants smoked an average of 16.9 cigarettes per day. As expected, there were substantial differences between the two samples, with those in the information seeker sample more highly motivated to quit.