Table 2.
Summary of results.
| Outcome | Quality of the evidence |
Effect Estimate (95% CI) | Quality (GRADE) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Study design | No of participants (studies) | Risk of bias | Inconsistency | Indirectness | Imprecision | Publication Bias | |||
| Thromboembolic events | RCT | 838 (5 studies) | Serious risk of bias, downgrade one level | Low heterogeneity | Not appear to be an issue | Some imprecision exists: Few events | Observed asymmetry in funnel plot | OR: 0.36 (0.11‒1.19) | ⊕⊕OO Low |
| Estimated total blood loss | RCT | 838 (5 studies) | Serious risk of bias, downgrade one level. | Substantial heterogeneity | Not appear to be an issue | Some imprecision exists: Few events and wide confidence intervals | Observed asymmetry in funnel plot | MD:-135.79 ( -179.50 to -92.08) | ⊕⊕OO Low |
| Need for blood transfusion | RCT | 838 (5 studies) | Serious risk of bias, downgrade one level. | Substantial heterogeneity | Not appear to be an issue | Some imprecision exists: Few events | Observed asymmetry in funnel plot | OR = 0.45 (0.32‒0.65) | ⊕⊕OO Low |
RCT, randomized clinical trials; CI, confidence interval; MD, mean difference; OR, odds ratios.
GRADE of evidence: high quality, the true effect lies close to that of the estimate of the effect; moderate quality: 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 quality: the true effect may be substantially different from the estimate of the effect; very low quality: the true effect is likely to be substantially different from the estimate of effect.