Table 2.

Research categories identified through the Cochrane Tobacco Addiction Group (CTAG) taps survey, their ranking and the top three ranking questions within each category.

Research category	Definition	No. of questions in category	Survey category ranking (n = 175)	n (question ranking)	Top 3 questions	Workshop category ranking (out of 8)
Addressing inequalities	Focus on reducing differences in tobacco use behaviour and health across groups, so that some groups do not have higher health risks than others, e.g. low‐ versus high‐income groups	8	2	73	1. What are the most effective stop smoking interventions for smokers who are part of a hard‐to‐reach group? 2. Which interventions reduce the difference in the number of smokers in low socio‐economic compared with high socio‐economic groups most effectively? 3. Which interventions are the most effective to help people stop smoking in communities where smoking as a group has cultural and social value?	1
Alternative tobacco products	Focus on products other than cigarettes that contain tobacco, e.g. snus, chewing tobacco and waterpipes	12	9	37	1. Why do some people use more than one type of tobacco product? 2. How safe is snus compared to other tobacco products and electronic cigarettes, and is it more dangerous if used alongside cigarettes? 3. Are there ways to stop young people from using nicotine and tobacco products other than cigarettes?	–
Digital interventions	Focus on digital interventions, i.e. any intervention accessed and used by tobacco users in the form of a computer, mobile phone or internet‐based programme or app	7	14	14	1. How effective and cost‐effective are mobile smart phone and internet apps in helping people to quit smoking? 2. Do individual or group‐based mobile smartphone interventions help more people to quit smoking? 3. Can mobile phones be used to help people to stick with their treatment while taking part in stop smoking studies?	–
Electronic cigarettes	Focus on e‐cigarettes: battery‐operated devices designed to deliver nicotine to users, without tobacco Nicotine is based within a liquid which is turned into a vapour	19	1	70	1. How safe are e‐cigarettes, and are they as safe as other products? 2. How can we educate people effectively about the risks and benefits of using e‐cigarettes? 3. Are e‐cigarettes an effective and cost‐effective aid to help people to stop smoking, and are they as effective as other products?	3/4
llness and chronic disease sufferers	Focus on tobacco users who have a short‐ or long‐term illness	5	8	22	1. What is the most effective and cost‐effective stop smoking intervention for smokers with long‐term medical problems? 2. If smokers with illnesses that may be made worse by smoking are referred to stop smoking services does this help them to quit? 3. What is the most effective and cost‐effective stop smoking intervention for smokers who are obese and have type 2 diabetes?	–
Initiating quit attempts	Focus on a tobacco user's decision to quit using tobacco	3	4	29	1. What is the most effective way to make people want to quit smoking? 2. What makes people decide to quit smoking? 3. Why has the number of people who are trying to quit smoking reduced in the United Kingdom?	3/4
Medications	Focus on medications used to help people change their tobacco use	16	15	14	1. What is the most effective medication current smokers, who do not want to quit, can use to reduce their tobacco use, and what is the best way to use it? 2. What are the most effective medications or combinations of medications to help people to quit smoking and how should they be used? 3. What is the most effective and cost‐effective way to use NRT (dose, length of use, etc.) so that people do not relapse to smoking after they have quit?	–
Mental health and other substance abuse	Focus on tobacco users with mental health problems and/or other substance abuse issues (e.g. cannabis or alcohol abuse), or to investigate issues related to mental health	13	3	43	1. How can we encourage and help mental health workers to offer stop smoking services to their patients with mental illness? 2. What is the most effective and cost‐effective way to help people with mental health problems to quit smoking inside and outside of mental health treatment settings? 3. What is the most effective and cost‐effective way to help people who also have drug and alcohol problems to quit smoking?	5/6
Nicotine and tobacco risk	Focus on risks, associated health problems and addiction potential of tobacco and nicotine; including ways to reduce harm in tobacco users who cannot quit (harm reduction)	11	10	28	1. How safe is nicotine when it is delivered in non‐tobacco products, and how does this compare to when it is delivered in tobacco products? 2. How addictive is nicotine, and how does this compare between different nicotine products (e.g. smoking tobacco, other tobacco products, e‐cigarettes, nicotine replacement therapy)? 3. If smokers reduce the number of cigarettes they smoke does this reduce the harm caused by their smoking?	–
Population‐level interventions	Focus on interventions related to tobacco use, targeting whole populations rather than individuals, e.g. government policies	21	5	34	1. Are any current interventions aimed at the general population effective in reducing the number of people who smoke and the harms linked to tobacco use? If so, which ones? 2. Does plain packaging stop people from taking up smoking? 3. Do interventions which aim to change tobacco related social norms reduce the demand for tobacco?	7/8
Pregnancy	Focus on tobacco use and quitting during pregnancy	10	6	27	1. How safe are e‐cigarettes when used during pregnancy, and are they as safe as other products? 2. What are the most effective and cost‐effective methods pregnant smokers can use to give up smoking? 3. Are e‐cigarettes an effective and cost‐effective aid to help people to stop smoking during pregnancy, and are they as effective as other products?	7/8
Smoking bans and second‐hand smoke	Focus on tobacco smoking bans and the second‐ and third‐hand smoke given off by cigarettes	11	13	19	1. Is the amount of second‐hand smoke people are exposed to linked to the effect this has on their health? 2. If smoking was banned in all public places would this have an effect on the number of people smoking and the health problems linked to smoking? 3. What are the most effective interventions to reduce the amount of second‐hand smoke present in flats and apartment buildings?	–
Smoking treatment methods excluding medications	Focus on any treatment methods for tobacco use, apart from treatments in the form of medications, but including research into behavioural support interventions	20	11	17	1. Does the amount of behavioural support a smoker receives influence how likely they are to quit? If so, how intensive does support need to be to result in success? 2. Which elements of behavioural support are most effective to help people quit tobacco use? 3. How effective are different stop smoking treatments when provided in the ‘real world’?	–
Treatment delivery	Research focusing on the best ways to deliver treatment for tobacco dependence	13	12	21	1. How can we make sure that all health‐care providers provide stop smoking treatment which research has been found to be effective, safe and cost‐effective? 2. What type of health providers provide the most effective support to help people to quit smoking, and how much training do they need to be most effective? 3. What are the most effective interventions that can be used in primary care (e.g. doctors' and dentists' surgeries, pharmacies) to encourage more people to use stop smoking services and to give up smoking?	2
Young people	Research focusing on tobacco uptake, use and treatment in young people	14	7	31	1. What is the most effective and cost‐effective way to stop young people from starting to smoke, in particular those in hard‐to‐reach groups? 2. Are there effective interventions to stop early trials of smoking from turning into tobacco addiction? 3. How can we stop the children of smokers from starting to smoke themselves?	5/6