© 2017 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction. Background and Aims: The Cochrane Tobacco Addiction Group (TAG) conducts systematic reviews of the evidence for tobacco cessation and prevention interventions. In 2016 TAG conducted a priority-setting, stakeholder engagement project to identify where further research is needed in the areas of tobacco control and smoking cessation. Design: The project comprised two surveys and a workshop. A range of stakeholders participated, including members of the public (smokers and ex-smokers), clinicians, researchers, research funders, health-care commissioners and public health organizations. The first survey phase identified unanswered research questions in the field of tobacco control. The second phase asked participants to rank these, with overall rankings calculated by combining scores across participants. The workshop allowed attendees to discuss prioritization of topics and questions in more depth. Workshop discussions were transcribed and analysed thematically, and a final voting activity at the close of the workshop allowed participants to choose topics to prioritize and to de-prioritize. Findings: A total of 304 stakeholders (researchers, health professionals, smokers and ex-smokers, guideline developers, research funders and policymakers, representing 28 countries) identified 183 unanswered research questions. These were categorized into 15 research categories. A total of 175 participants prioritized categories and questions in the second survey phase, with ‘electronic cigarettes’; ‘addressing inequalities’; and ‘mental health and other substance abuse’ prioritized as the top three categories. Forty-three stakeholders attended the workshop and discussed reasons for and against category prioritization. Prioritized research categories largely mirrored those in the survey stage, although ‘treatment delivery’ also emerged as a key category. Five cross-cutting themes emerged: efficacy; relative efficacy; cost effectiveness; addressing inequalities; and different types of evidence. Conclusions: There are many unanswered questions in the field of tobacco control. Stakeholders highlighted electronic cigarettes, addressing inequalities and mental health and other substance abuse as key areas for further research, and efficacy, relative efficacy, cost-effectiveness and use of non-randomized studies as important themes cutting across research areas. Future prioritization work would benefit from targeting non-US and non-UK stakeholders explicitly and from examining where priorities may differ based on stakeholder group.
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