The data collection period for Wave 7 occurred between October 2008 and June 2009 and for Wave 8 between July 2010 and February 2011. The mean Wave 7�C8 interwave interval selleck chem inhibitor was 611 days (SD = 45 days). Further detail on ITC methodology is available in Thompson et al. (2006). We excluded from the sample described above anyone who did not report making any attempts to quit smoking during the interval between the two surveys (n = 2,288) and anyone who had made an attempt but was currently still quit at the Wave 8 survey (n = 429). We also excluded participants who could not provide valid data on their use of SSMs on their last quit attempt (n = 34) or on the length of time ago that their last quit attempt had started (n = 36). One thousand one hundred and one adults (60.0% female; mean age = 48.

1 years, SD = 12.8 years) met our final selection criteria. Measures Use of SSMs on the last quit attempt was coded into three categories: (a) no medications used; (b) only NRT used; and (c) any prescription SSMs used, by cross-tabulating responses to the following three questions: On your last quit attempt, did you use any type of nicotine replacement therapy? (n = 405 responded ��yes��) On your last quit attempt, did you use Bupropion, also called Zyban? (n = 57 responded ��yes��) On your last quit attempt, did you use Varenicline, also called Champix or Chantix? (n = 194 responded ��yes��) Participants reporting use of both NRT and Bupropion or Varenicline were coded into Category (c).

The time (in days) since participants�� last quit attempt was assessed by asking, ��When did your most recent quit attempt start?�� SSM use and start of the last quit attempt were all assessed at the follow-up wave (Wave 8). To estimate baseline levels of addiction, we also calculated the Heaviness of Smoking Index (HSI: Heatherton, Kozlowski, Frecker, Rickert, & Robinson, 1989) from the reported number of cigarettes smoked per day and minutes to first cigarette of the day at the baseline wave (Wave 7: 3.2% missing). HSI scores range from 0 (least addicted) to 6 (most addicted). Analyses We examined the prevalence of over-the-counter NRT and Rx SSM use on the most recent failed quit attempt and report 95% C I. We also computed mean levels of HSI and Brefeldin_A recalled time since the start of the last quit attempt across the three SSM use groups. We conducted a 3 (SSM group) �� 7 (HSI levels) analysis of variance (ANOVA) to determine whether levels of addiction influenced the recalled time since the start of the last quit attempt. We explored these relationships both including and excluding participants who smoked less than 10 cigarettes/day at baseline (n = 344), as use of SSMs is not generally recommended as a quitting strategy for this group.