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Table 3 Inclusion and exclusion criteria for an updated review on e-cigarettes

From: Effectiveness of stop smoking interventions among adults: protocol for an overview of systematic reviews and an updated systematic review

  Inclusion Exclusion
Population Adults (≥ 18 years) who are current tobacco smokers (as defined by a given study) ▪ Studies exclusively in children/adolescents (i.e. under 18 years old)
▪ Studies that involve interventions targeted to adults other than the tobacco smoker (e.g. partners, healthcare providers)
Intervention • Nicotine or non-nicotine containing e-cigarettesa
• Nicotine or non-nicotine containing e-cigarettes combined with other smoking cessation treatment (behaviour and/or pharmacological)
Studies exclusively examining short-term use of nicotine or non-nicotine containing e-cigarettes (i.e. < 1 week)
Comparator KQ2a:
▪ Non-nicotine containing e-cigarettes (i.e. placebo e-cigarettes)
▪ No intervention
▪ Usual/standard care
▪ Waitlist
▪ Minimal intervention
• Alternative nicotine containing e-cigarettes (e.g. different generation e-cigarette or e-cigarette containing a different dose of nicotine)
• Non-nicotine containing e-cigarettes
• Other smoking cessation aids (e.g. nicotine replacement therapy)
Studies exclusively examining short-term use of nicotine or non-nicotine containing e-cigarettes (i.e. < 1 week)
Outcomes Critical
• Tobacco use abstinence (as defined in the study)
• Reduction in tobacco smoking frequency/quantity
• Relapse (KQ2b only)b
• Quality of life (using validated scales)
• Adverse events (as defined in a given review)
• Possible adverse outcomes:
o Weight gain
o Changes in emotional state (e.g. increases in anxiety, changes in mood, irritability)
o Loss of social groupc
Timing of outcome assessment For abstinence/relapse, and quality of life outcomes: Minimum 6 months from quit date (if reported) or from initiation of intervention (if quit date not specified)
All other outcomes:
• Any point after initiation of intervention
Setting Settings that could serve as the primary point of contact for individuals to receive smoking cessation advice, including:
Family medicine clinics
Walk-in clinics
• Smoking cessation clinics
• Urgent care facilities
• Emergency departments
• Public health units
• Pharmacies
• Dental offices
• Behavioural health/substance use treatment facilities (ambulatory or outpatient)
• Telehealth
• Academic research settings
▪ Studies in settings not relevant to primary care including workplaces, schools, inpatient settings, and medical specialist settings
▪ Studies that take place in countries “high”, “medium”, or “low” on the Human Development Index
Study design For benefits:
• Randomized controlled trials
For harms:
• Randomized controlled trials
• Non-randomized controlled trials
• Comparative observational study designs (e.g. prospective and retrospective cohort studies, case-control studies)
For benefits:
• Non-randomized controlled trials
• Observational study designs
For harms:
• Non-comparative studies
• Cross-sectional studies
For benefits and harms:
• Systematic reviews
• Case reports, case series
• Editorials
• Commentaries
Language ▪ English
▪ French
Dates of publication ▪ Date of last search of the review to present date  
  1. aNicotine and non-nicotine containing e-cigarettes can serve as either an intervention or comparator
  2. bThe outcome “relapse” was initially considered critical based on WG rating. However, based on discussion with WG members, it was decided that this outcome should be considered important. It was also decided that this outcome is most important for KQ1b
  3. cAlthough initially rated as being of limited importance by the WG, based on discussions with WG members, it was decided that this outcome should be considered as important. Clinical experts and patients rated this outcome as important