for the main comparison.
| Smokefree Class Competitions (SFC) for preventing smoking uptake | |||||
|
Patient or population: Children and adolescents aged 5 ‐ 18 years who were non‐smokers at baseline Settings: Schools in Germany, the Netherlands, Finland, Switzerland, Canada and the United States Intervention: Participation in SFC Comparison: No participation in SFC | |||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) |
No of Participants Actual number/ effective number2 (studies) |
Quality of the evidence (GRADE) | |
| Assumed risk1 | Corresponding risk | ||||
| Smoking uptake at longest follow‐up (RCTS) | 317 per 1000 | 320 per 1000 | RR 1.00 (0.84 to 1.19) | 3056/1108 (3) |
Low3, 4 |
| Smoking uptake at longest follow‐up (Non‐RCTs) |
158 per 1000 | 132 per 1000 | RR 0.82 (0.63 to 1.08) | 4219/1377 (3) |
Very low3, 5, 6 |
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: Confidence interval; RR: Risk Ratio; RCT: Randomised Controlled Trial | |||||
| 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. | |||||
1'Assumed risk' calculated as risk in control groups. 2Adjusted for clustering. 3Downgraded one level due to imprecision. All studies included had a wide confidence interval. 4Downgraded one level due to risk of bias. 2/3 studies judged to be at high risk of attrition bias. 5Downgraded one level due to observational (non‐RCT) study type. 6Downgraded one level due to risk of bias. 2/3 studies judged to be at high risk of selection bias, most other bias risks unclear.