Summary of findings 15. Safety: asthma.
| Safety: asthma | |||||
| Patient or population: children 9 months to 15 years old Setting: general population Intervention: MMR vaccine Comparison: unvaccinated | |||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | |
| Risk of asthma amongst unvaccinated | Risk of asthma amongst vaccinated | ||||
| Cohort study (rate ratio) ‐ all ages | Study population | Rate ratio 1.05 (0.80 to 1.39) | 1,067,712 (3 observational studies) | ⊕⊕⊝⊝ LOW | |
| 32 per 1000 | 33 per 1000 (25 to 44) | ||||
| Cohort studies (risk ratio) ‐ all ages | Study population | RR 0.63 (0.24 to 1.63) | 886 (3 observational studies) | ⊕⊕⊝⊝ LOW | |
| 414 per 1000 | 261 per 1000 (99 to 674) | ||||
| *The risk in the intervention group (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; MMR: measles, mumps, rubella vaccine; RR: risk ratio | |||||
| GRADE Working Group grades of evidence High certainty: We are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: We are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: Our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: We have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | |||||
1Upgraded one level due to non‐critical risk of bias in the study and large number of participants.