Table 1 Semi-structured interview guide

1. Can you describe to me what got you interested taking part in the PTQ II study?

2. What were you hoping to get out of taking part in the study?

3. What kinds of activities were you doing in the study?

4. You mentioned you received (education/sessions on smoking/sessions on smoking and alcohol) as part of the study. What was your overall impression of doing these activities?

5. How did you feel about the amount of education or counselling you received?

6. Did you use the patch/gum/lozenge? If you didn’t use them every day for 12 weeks, what were some of the things that kept you from doing so?

7. Were there any parts of the study activities you particularly liked?

8. Were there any parts of the study activities you particularly did not like?

9. How was it hard, or easy, to make it along to counselling sessions?

10. How would you have felt about it if you had been offered an opportunity to do the counselling by phone?

11. Did the sessions have any impact on your (smoking or smoking and drinking)?

12. What could have made the sessions even better for you?

13. In general, do you have any views on how dealing with homelessness impacts the ability of people to take part in studies like this?

14. Did the counselling sessions have any impact on other aspects of your life, aside from the smoking/smoking and drinking?

15. What did you think about the study questionnaires you were asked to complete?

16. What did you think about the incentives you received?

17. Finally what other topics do you think we should research to help us address smoking for people experiencing homelessness?