Grade summary of findings for Ware et al 201220
| Outcomes | Comparator arm Transfusions with chelation | Intervention arm Hydroxyurea with phlebotomy | Relative effect (95% CI) | No. of participants (studies) | Quality of the evidence (GRADE) | Comments |
|---|---|---|---|---|---|---|
| Secondary stroke recurrence recurrence rate Follow-up: 6 months | Recurrence rate of 0%, 0.0 events per 100 patient years in comparator arm versus recurrence rate of 10%, 5.6 events per 100 patient years in the intervention arm | Rate difference of 0.1 | 161 (1 study) | ⊕⊕⊝⊝ low†‡§¶ | ||
| Iron overload Liver Iron concentration mg/g dry weight liver Follow-up: 6 months | The median iron overload in the control groups was 17.3 mg/g dry weight liver (8.8–30.7 IQR) | The median iron overload in the intervention groups was 17.2 mg/g dry weight liver (10.0–30.6 IQR) | Change from baseline(median (IQR) −2.2 (−5.5 to 4.9) in the comparator group −1.2 (−2.8 to 7.2) in the intervention group | 161 (1 study) | ⊕⊕⊝⊝ low †‡§¶,**,†† | |
*Children enrolled in the study were above 5 years old yet interested in data of children below 5 years.
†The use of hydroxyurea overlapped at some point with transfusions during the dose escalation.
‡The study setting is in high-income setting where there is thorough laboratory monitoring in contrast with low-income setting that the study question focuses on.
§Some point estimates in the study have wide CIs.
¶Sample sizes in both arms were small (hydroxyurea with phlebotomy, n=67; while transfusions with chelation, n=66).
GRADE Working Group grades of evidence; High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate.
GRADE, Grading of Recommendations Assessment, Development and Evaluation.