Clinically important factors affecting transfusion outcomes
. | 1-hour platelet increment, × 109/L . | 18- to 24-hour platelet increment, × 109/L . | Refractoriness (hazard ratio) . | Days to next transfusion . |
|---|---|---|---|---|
| Factor | ||||
| Overall response | 24.9 | 12.0 | 1.75 | |
| Clinically important change | ≥ 5.0* | ≥ 2.4* | ≥ 2.0† | ≥ 0.35* |
| Improved platelet responses | ||||
| Splenectomy | +24.8‡ | +12.4‡ | - | - |
| ABO compatible | +4.6 | +6.3‡ | - | - |
| Decreased platelet responses | ||||
| Lymphocytotoxic antibody-positive | -9.3‡§ | -4.0‡ | 3.48‡ | -0.36‡ |
| Females with ≥ 2 pregnancies, and males | -8.9‡ | -5.7‡ | 2.78‡ | -0.40‡ |
| Palpable spleen | -3.5 | -4.4‡ | - | -0.23 |
| Heparin | - | -3.8‡ | 2.43‡ | -0.37‡ |
| Bleeding | -1.7 | -3.1‡ | 2.00‡ | -0.33 |
| Fever | -1.6 | -2.0 | 2.12‡ | -0.25 |
| Amphotericin | -2.7 | -2.5‡ | - | -0.28 |
| DIC | - | - | - | -0.40‡ |
. | 1-hour platelet increment, × 109/L . | 18- to 24-hour platelet increment, × 109/L . | Refractoriness (hazard ratio) . | Days to next transfusion . |
|---|---|---|---|---|
| Factor | ||||
| Overall response | 24.9 | 12.0 | 1.75 | |
| Clinically important change | ≥ 5.0* | ≥ 2.4* | ≥ 2.0† | ≥ 0.35* |
| Improved platelet responses | ||||
| Splenectomy | +24.8‡ | +12.4‡ | - | - |
| ABO compatible | +4.6 | +6.3‡ | - | - |
| Decreased platelet responses | ||||
| Lymphocytotoxic antibody-positive | -9.3‡§ | -4.0‡ | 3.48‡ | -0.36‡ |
| Females with ≥ 2 pregnancies, and males | -8.9‡ | -5.7‡ | 2.78‡ | -0.40‡ |
| Palpable spleen | -3.5 | -4.4‡ | - | -0.23 |
| Heparin | - | -3.8‡ | 2.43‡ | -0.37‡ |
| Bleeding | -1.7 | -3.1‡ | 2.00‡ | -0.33 |
| Fever | -1.6 | -2.0 | 2.12‡ | -0.25 |
| Amphotericin | -2.7 | -2.5‡ | - | -0.28 |
| DIC | - | - | - | -0.40‡ |
A clinically important change for 1-hour and 24-hour posttransfusion increments and days to next transfusion was considered to be a ≥ 20% difference from the overall responses observed in the trial
For the hazard ratio, an increase of ≥ 2.0 was considered clinically important
Value meets the criteria for a clinically important change. If a result is given but not noted with ‡, it is statistically significantly different but does not meet the clinically important criterium. If no value is listed (-), there was neither a clinically important nor statistically significant difference for the outcome measure
The platelet increment was estimated to be 9.3 × 109 less at 1 hour after transfusion for all study arms except UV-B (see the final paragraph under “Platelet increments”). The platelet increment was estimated to be 4.0 × 109 platelets/L less at 18 to 24 hours after transfusion for all arms