| Methods |
2001 to 2002 season data from Vesikari 2006 |
| Participants |
|
| Interventions |
|
| Outcomes |
|
| Funding Source |
Industry |
| Notes |
This second year could be biased due to attrition. |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Insufficient description |
| Allocation concealment (selection bias) |
Unclear risk |
Insufficient description |
| Blinding (performance bias and detection bias)
All outcomes |
Unclear risk |
Insufficient description |
| Incomplete outcome data (attrition bias)
All outcomes |
High risk |
The proportion of missing outcomes compared with observed event risk is enough to induce clinically relevant bias in intervention effect estimate. |
| Summary assessments |
High risk |
Some doubts arise from attrition bias. |
