Table 1.
Patient characteristics
| Characteristic | Overall SWiTCH | Rh immunized | Controls | P | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Mean ± SD | No. | Female (%) | Mean ± SD | No. | Female (%) | Mean ± SD | No. | Female (%) | ||
| No. of patients | 134 | 46 | 27 | 67 | 27 | 56 | NA | |||
| Age, y | ||||||||||
| At enrollment | 13.2 ± 3.9 | 14.9 ± 3.5 | 14.2 ± 3.1 | .44 | ||||||
| At first stroke | 5.9 ± 2.9 | 7.2 ± 3.9 | 6.6 ± 3.0 | .53 | ||||||
| Duration of transfusions, y | 7.2 ± 3.7 | 7.6 ± 4.6 | 7.6 ± 4.2 | 1.0 | ||||||
Among all 134 randomly assigned SWiTCH study participants, 27 children had documented Rh immunization at study entry. Controls were identified from nonimmunized SWiTCH participants and matched first for duration of transfusions (mean difference, 0.0 y; median difference, 0.0 y) and then for age at first stroke (mean difference, 0.6 y; median difference, 0.0 y). Sex was matched when possible.
NA, not applicable; SD, standard deviation.