, 2005). Although we did not have specific recruitment goals, we purposefully sellekchem targeted a diversity of communities and monitored the demographic characteristics of the sample to ensure a diverse sample. Given that lower income and racial minority groups are disproportionately represented in the smoking population (Centers for Disease Control and Prevention, 1998, 2010), it is encouraging that results suggest that SMS USA has the potential to be especially beneficial to these groups. This is one of the few studies to test a text messaging�Cbased program against a blinded control group. Content was intentionally designed not to include components necessary to affect cessation (e.g., preparation for quitting) and instead talked about the importance of quitting within the context of improving one��s fitness and sleep.

Three in four control participants said that the messages talked about what they were feeling and experiencing, suggesting that participants were successfully blinded with content that had perceived utility, yet provided insufficient transfer of skills for cessation. The observed difference in cessation rates between the two study groups is the first evidence to support the hypothesis that above and beyond the simple act of text messaging, content does matter when trying to affect cessation. Text messaging is simply the delivery mode; it is not the intervention itself. As with other delivery mechanisms (e.g., in-person, online), the messaging content is key to affecting behavior change.

That said, it is curious that the cessation rate among intervention participants was stable between 4 weeks and 12 weeks, but increased among control participants. Batimastat Unfortunately, we do not have data about the quitting experience for these newly quit control participants. Perhaps they were able to try quitting again as a result of improving their fitness and sleep first. Perhaps it is a function of small sample size (i.e., a few people moving into the ��quit�� category has a larger impact on the overall percentage of people who are quit). Limitations The main limitation of the study is its small sample size. As a feasibility study, it was not powered to detect differences in effects between the two arms. This is especially true for the six subgroup analyses conducted. Also, it is unclear how young adult smokers recruited on Craigslist compared with young adult smokers who would be recruited through other ways, particularly those who would enroll in a text-messaging program if it were publicly available. Additionally, there were problems with the randomization program, which resulted in manual assignment of the final eight participants to balance allocations.