Summary of findings 3. Long‐term RBC transfusions compared to standard care for SCD‐related SAEs and clinical stroke in people with SCD at risk of stroke and no previous long‐term RBC transfusions.
| Long‐term RBC transfusions compared to standard care for SCD‐related SAEs and clinical stroke in people with SCD at risk of stroke and no previous long‐term RBC transfusions | ||||||
| Patient or population: SCD‐related SAEs and clinical stroke in people with SCD at risk of stroke and no previous long‐term RBC transfusions Setting: outpatient Intervention: long‐term RBC transfusions Comparison: standard care | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with standard care | Risk with long‐term RBC transfusions | |||||
| SCD ‐ related SAEs ‐ ACS | Trial population | RR 0.24 (0.12 to 0.49) | 326 (2 RCTs) | ⊕⊕⊝⊝ LOW 1 2 | ||
| 232 per 1000 | 56 per 1000 (28 to 114) | |||||
| SCD‐related SAEs ‐ pain crisis | Trial population | RR 0.63 (0.42 to 0.95) | 326 (2 RCTs) | ⊕⊕⊝⊝ LOW 1 2 | ||
| 421 per 1000 | 265 per 1000 (177 to 400) | |||||
| Clinical stroke | Trial population | RR 0.12 (0.03 to 0.49) | 326 (2 RCTs) | ⊕⊕⊕⊝ MODERATE 1 | ||
| 110 per 1000 | 13 per 1,000 (3 to 54) | |||||
| *The risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). ACS: acute chest syndrome: CI: confidence interval; RR: risk ratio; RBC: red blood cells; RCT: randomised controlled trial; SAEs: serious adverse events; SCD: sickle cell disease | ||||||
| GRADE Working Group grades of evidence High quality: we are very confident that the true effect lies close to that of the estimate of the effect Moderate quality: 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 quality: our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low quality: we have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect | ||||||
a Data for the other outcomes for this SoF table are presented separately in Table 1 (normal TCD velocities) and Table 2 (abnormal TCD velocities) We combined the data for these specific comparisons as they are objective outcomes and the status of TCD velocities does not impact these outcomes.
1 We downgraded the quality of the evidence by 1 due to risk of bias. Unblinded trial and cross‐overs, and imbalance between loss to follow‐up between trial arms
2 We downgraded the quality of the evidence by 1 due to indirectness (only children with HbSS or HbSβº thalassaemia included in studies). If this review was only considering the quality of evidence for children with HbSS the quality of evidence would not have been downgraded for indirectness.