Table 4.
Multiparameter model of days from first platelet transfusion to grade 2 or higher bleeding
| Characteristic | N | Hazard ratio | 95% CI | P |
|---|---|---|---|---|
| Platelet dose group | .28 (2 df) | |||
| LD | 220 | 0.75 | 0.45-1.25 | .27 |
| MD | 216 | Referent category | ||
| HD | 201 | 1.12 | 0.72-1.75 | .62 |
| Platelet source | .68 (1 df) | |||
| Apheresis | 507 | Referent category | ||
| WBP | 130 | 1.11 | 0.67-1.85 | .68 |
| ABO matching status | .36 (2 df) | |||
| ABO-identical | 395 | Referent category | ||
| Minor mismatch | 67 | 1.07 | 0.57-2.01 | .83 |
| Major mismatch | 175 | 0.72 | 0.44-1.18 | .19 |
| Storage duration, d | 1.00 (3 df) | |||
| 0-2 | 48 | 0.99 | 0.44-2.20 | .98 |
| 3 | 156 | Referent category | ||
| 4 | 216 | 1.06 | 0.64-1.76 | .83 |
| 5 | 217 | 1.02 | 0.62-1.70 | .93 |
The frailty model includes platelet dose, source, matching status, and storage duration, and is also adjusted for patient sex, patient age group, patient treatment category, and site (with site treated as a random effect). Data on time to bleeding were censored if any of the following occurred before the patient experienced grade 2 or higher bleeding: a transfusion that differed from the patient's first transfusion in source, matching status, or storage duration or had missing data on one of those characteristics; a day with missing data on whether grade 2 or higher bleeding had occurred; or end of study. Overall, 83.2% of patients had censored data.
N indicates number of evaluable patients; LD, low dose; MD, medium dose; HD, high dose; and WBP, whole blood platelet.