Table 3.
GRADE summary of findings.
|
Patient or population adults and children with cardiac arrest in the out-of-hospital setting Intervention community-based interventions (CBIs) with or without health system interventions (HSIs) Comparison prior to or without CBIs or HSIs | |||||
|---|---|---|---|---|---|
| Outcomes | № of participants (studies) Follow up | Certainty of the evidence (GRADE) | Relative effect (95% CI) | Anticipated absolute effects | |
| Risk prior to CBIs or HSIs | Risk difference after CBIs or HSIs | ||||
| Bystander-CPR rates (critical outcome) | 285,752 (14 observational studies) |
⨁⨁◯◯ LOW*,†,‡,§ |
OR 2.26 (1.74 to 2.94) | 339 per 1000 | 198 more per 1000 (133 to 262 more) |
| Survival rates (critical outcome) | 79,206 (10 observational studies) |
⨁◯◯◯ VERY LOW*,†,§ |
OR 1.59 (1.20 to 2.10) | 90 per 1000 | 46 more per 1000 (16 to 82 more) |
| Survival with favorable neurological outcome rates (critical outcome) | 272,882 (8 observational studies) |
⨁◯◯◯ VERY LOW*,†,§ |
OR 1.42 (1.06 to 1.90) | 22 per 1000 | 9 more per 1000 (1 to 19 more) |
| Bystander-AED rates (important outcome) | 37,882 (5 observational studies) |
⨁◯◯◯ VERY LOW* |
OR 2.08 (1.44 to 3.01) | 21 per 1000 | 22 more per 1000 (9 to 39 more) |
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, OR odds 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.
*Serious risk of bias: failure to adequately control or adjust for confounding factors due to study design.
†Serious inconsistency: considerable heterogeneity present (defined as I-squared 75–100%); some but not all heterogeneity explained with sub-group analysis.
‡Upgraded for strong association.
§Upgraded for dose–response relationship.