Table 1.
Assessment of the quality of evidence of RCTs included in the meta-analyses, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach
| Studies | Certainty assessment |
Proportion with event
*
|
Effect
†
|
Certainty | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Risk of bias | Inconsistency | Indirectness | Imprecision | Other | RIPC | Control/sham | Relative | Absolute | ||
| Cardiovascular events | ||||||||||
| 13 RCTs | Not serious | Serious‡ | Not serious | Not serious | Publication bias strongly suspected§ | 167 of 949 (17.6) | 254 of 1019 (24.9) | OR 0.68 (0.47, 0.96) | 65 fewer (from 114 to 8 fewer) per 1000 | Low |
| Acute kidney injury | ||||||||||
| 12 RCTs | Not serious | Not serious¶ | Not serious | Not serious | None | 110 of 603 (18.2) | 101 of 605 (16.7) | OR 1.14 (0.78, 1.69) | 19 more (from 32 fewer to 86 more) per 1000 | High |
| Mortality ≤ 90 days | ||||||||||
| 7 RCTs | Not serious | Not serious | Not serious | Very serious# | None | 27 of 619 (4.4) | 38 of 620 (6.1) | OR 0.65 (0.37, 1.12) | 21 fewer (from 38 fewer to 7 more) per 1000 | Low |
| Mortality > 90 days | ||||||||||
| 4 RCTs | Not serious | Not serious | Not serious | Very serious# | None | 3 of 585 (0.5) | 6 of 582 (1.0) | OR 0.67 (0.18, 2.55) | 3 fewer (from 8 fewer to 16 more) per 1000 | Low |
Values in parentheses are
*
percentages and
†
95 per cent confidence intervals.
‡
I 2 = 41 per cent.
§
Funnel plot asymmetrical.
¶
I 2 = 9 per cent.
#
Small number of events, wide confidence interval. RIPC, remote ischaemic preconditioning; OR, odds ratio.