Table 2. GRADE evidence profile.
| Quality assessment |
No of patients |
Effect |
Quality | Importance | |||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No of studies | Design | Risk of bias | Inconsistency | Indirectness | Imprecision | Other considerations | Mechanical chest compressions | Manual chest compressions | Relative (95% CI) | Absolute | |||||||||||||||||
| Survival with good neurological outcome to hospital discharge | |||||||||||||||||||||||||||
| 4 | randomized trials | serious1 | serious2 | no serious indirectness | no serious imprecision | none | 284/5445 (5.2%) | 408/6613 (6.2%) | RR 0.8 (0.61 to 1.04) | 12 fewer per 1000 (from 24 fewer to 2 more) | LOW | CRITICAL | |||||||||||||||
| 6.7% | 13 fewer per 1000 (from 26 fewer to 3 more) | ||||||||||||||||||||||||||
| Survival to hospital admission | |||||||||||||||||||||||||||
| 5 | randomized trials | serious1 | no serious inconsistency | no serious indirectness | no serious imprecision | none | 1460/5680 (25.7%) | 1820/6830 (26.6%) | RR 0.94 (0.89 to 1) | 16 fewer per 1000 (from 29 fewer to 0 more) | MODERATE | IMPORTANT | |||||||||||||||
| 23.7% | 14 fewer per 1000 (from 26 fewer to 0 more) | ||||||||||||||||||||||||||
| Survival to hospital discharge | |||||||||||||||||||||||||||
| 5 | randomized trials | serious1 | no serious inconsistency | no serious indirectness | no serious imprecision | none | 463/5680 (8.2%) | 605/6830 (8.9%) | RR 0.88 (0.78 to 0.99) | 11 fewer per 1000 (from 1 fewer to 19 fewer) | MODERATE | IMPORTANT | |||||||||||||||
| 9.6% | 12 fewer per 1000 (from 1 fewer to 21 fewer) | ||||||||||||||||||||||||||
| Return of spontaneous circulation | |||||||||||||||||||||||||||
| 3 | randomized trials | serious3 | no serious inconsistency | no serious indirectness | no serious imprecision | none | 1012/3027 (33.4%) | 1354/4181 (32.4%) | RR 1.02 (0.95 to 1.09) | 6 more per 1000 (from 16 fewer to 29 more) | MODERATE | IMPORTANT | |||||||||||||||
| 31.5% | 6 more per 1000 (from 16 fewer to 28 more) | ||||||||||||||||||||||||||
| Long-term (≥6 months) survival | |||||||||||||||||||||||||||
| 2 | randomized trials | serious3 | no serious inconsistency | no serious indirectness | no serious imprecision | none | 200/2952 (6.8%) | 279/4108 (6.8%) | RR 0.96 (0.79 to 1.16) | 3 fewer per 1000 (from 14 fewer to 11 more) | MODERATE | IMPORTANT | |||||||||||||||
| 7.1% | 3 fewer per 1000 (from 15 fewer to 11 more) | ||||||||||||||||||||||||||
1Only two trials were judged to be at low risk of bias.
2Substantial heterogeneity (I2 = 65%) was found.
3Only one trial was judged to be at low risk of bias.