Etter JF, Bullen C. Electronic cigarette : users profile, utilization, satisfaction and perceived efficacy. Addiction 2011 DOI: 10.1111/j.1360-0443.2011.03505.x.

“Findings.  There were 3587 participants (70% former tobacco smokers, 61% men, mean age 41 years). The median duration of electronic cigarette use was 3 months, users drew 120 puffs/day and used 5 refills/day. Almost all (97%) used e-cigarettes containing nicotine. Daily users spent $33 per month on these products. Most (96%) said the e-cigarette helped them quit smoking or reduce their smoking (92%). Reasons for using the e-cigarette included the perception it was less toxic than tobacco (84%), to deal with craving for tobacco (79%) and withdrawal symptoms (67%), to quit smoking or avoid relapsing (77%), because it was cheaper than smoking (57%) and to deal with situations where smoking was prohibited (39%). Most ex-smokers (79%) feared they might relapse to smoking if they stopped using the e-cigarette. Users of nicotine-containing e-cigarettes reported better relief of withdrawal and a greater effect on smoking cessation than those using non-nicotine e-cigarettes.

Conclusions.  E-cigarettes were used much as people would use nicotine replacement medications: by former smokers to avoid relapse or as an aid to cut down or quit smoking. Further research should evaluate the safety and efficacy of e-cigarettes for administration of nicotine and other substances, and for quitting and relapse prevention.”

http://onlinelibrary.wiley.com/doi/10.1111/j.1360-0443.2011.03505.x/abstract 

McQueen A, Tower S, Sumner W. Interviews With “Vapers”: Implications for Future Research With Electronic Cigarettes. Nicotine & Tobacco Research 2011. doi: 10.1093/ntr/ntr088.

“Methods: Participants attended a convention or club meeting in St. Louis, MO, and were interviewed individually or in small groups. Qualitative methods were used to analyze interview data for both deductive and emergent themes to broad research questions.

Results: Even with a relatively small sample of formal participants (N = 15), there were pervasive themes including the language and culture of vaping; social and informational support among vapers and their use of Internet resources (learning about e-cigs); the learning curve to using e-cigs and the numerous modifications (“mods???) available for e-cigs and personal vaporizers; motives and perceived benefits of using e-cigs versus cigarettes including cigarette-like enjoyment, cost, restored sense of taste and smell, and improved breathing and exercise tolerance; rapidly reduced nicotine tolerance and dependence; and a strong interest in e-cig??”related research and policy. “

http://ntr.oxfordjournals.org/content/early/2011/05/12/ntr.ntr088.abstract

Siegel MB, Tanwar KL, Wood KS. Electronic cigarettes as smoking cessation tool: Results from an Online Survey. American Journal of Preventive Medicine 2011 Apr; 40(4):472-5.

“This study aimed to examine the effectiveness of e-cigarettes for smoking cessation using a survey of smokers who had tried e-cigarettes. Using as a sampling frame a cohort of all first-time purchasers of a particular brand of e-cigarettes during a 2-week period, a cross-sectional, online survey was conducted. The primary finding was that the 6-month point prevalence of smoking abstinence among the e-cigarette users in the sample was 31.0% (95% CI=24.8%, 37.2%). A large percentage of respondents reported a reduction in the number of cigarettes they smoked (66.8%) and almost half reported abstinence from smoking for a period of time (48.8%). Those respondents using e-cigarettes more than 20 times per day had a quit rate of 70.0%. Of respondents who were not smoking at 6 months, 34.3% were not using e-cigarettes or any nicotine-containing products at the time. Findings suggest that e-cigarettes may hold promise as a smoking-cessation method and that they are worthy of further study using more-rigorous research designs.”

http://www.ajpm-online.net/webfiles/images/journals/amepre/AMEPRE3013.pdf