Table 2.
Summary of findings table
| Nicotine-containing Electronic cigarettes (ENDS) vs Nicotine Replacement Therapies (NRT) for smoking cessation | ||||
| Population: current smokers at enrolment into trials | ||||
| Intervention: Nicotine-containing e-cigarettes | ||||
| Comparison: Nicotine-replacement therapies | ||||
| Outcomes ENDS as compared with NRT |
Relative effect (95% CI) |
No of participants (studies) | Quality of the evidence (GRADE) | Comments |
| Cessation | RR 1.42 (0.97 to 2.09) | 1800 (5 studies) | ⊕⊕OO*† low |
|
|
Smoking reduction Proportion of people decreasing cigarette consumption by 50% Mean decrease in cigarettes per day |
RR 1.25 (0.79 to 1.98) MD 1.11 (-0.41 to 2.63) |
1460 (4 studies) 633 (3 studies) |
⊕⊕OO*† low ⊕⊕OO*† low |
|
| Adverse events (AEs) | RR 0.96 (0.76 to 1.20) | 758 (4 studies) | ⊕OOO*†‡ Very low |
No severe AEs related to investigated products were reported |
| Withdrawal symptoms | Summary data not available | 4 studies | ⊕OOO*†‡ Very low |
Withdrawal measures included Minnesota Nicotine Withdrawal Scale, QSU scores, frequency of urge and strength of urge score and prespecified symptoms of depressed mood, irritability, restlessness and hunger |
| Acceptance of therapy | Summary data not available | 4 studies | ⊕OOO*†‡ Very low |
Acceptance defined as wanting to recommend product to friends, helpfulness, taste, satisfaction, psychological reward, enjoyment of sensation, aversion, and ability to reduce craving depending on study |
GRADE Working Group grades of evidence.
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.
*Downgraded one level because of risk of bias.
†Downgraded one level because of heterogeneity.
‡Downgraded one level because of imprecision of results.
GRADE, Grading of Recommendations Assessment, Development and Evaluation; MD, mean difference; QSU, Questionnaire on Smoking Urges; RR, rate ratio.