| Methods |
Design: three group parallel trial
Purpose: examine the effect of nicotine chewing gum treatment on smoking |
| Participants |
Patients: smokers
Baseline comparability: yes |
| Interventions |
Placebo: chewing gum without nicotine
Untreated: no chewing gum
Experimental: chewing gum with nicotine
(Co‐intervention: NS) |
| Outcomes |
Number of abstinent smokers (based on carboxyhaemoglobin levels)
Number of abstinent smokers (based on self report) |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Adequate sequence generation? |
Unclear risk |
NS |
| Allocation concealment? |
Unclear risk |
NS |
| Blinding?
Treatment provider |
Low risk |
'The trial was double blind between the gum groups' |
| Blinding?
Outcome assessor |
Unclear risk |
NS |
| Incomplete outcome data addressed?
All outcomes |
High risk |
Drop‐out > 15% or NS |
| Free of selective reporting? |
Unclear risk |
No protocol available |
| Free of other bias? |
Low risk |
|
| No signs of variance inequality or skewness? |
Unclear risk |
Not relevant (binary outcome) |
| Trial size > 49? |
Low risk |
N = 121 |
| Clearly concealed allocation + trial size > 49 + drop‐out max 15% |
High risk |
Drop‐out > 15% or NS |
