Randomised trials published before 2020 comparing higher and lower haemoglobin transfusion thresholds for preterm infants
| Transfusion threshold group | Iowa trial5 | PINT trial6 | Taiwan trial20 | |||
| Higher | Lower | Higher | Lower | Higher | Lower | |
| Highest haemoglobin threshold,* g/dL | 15.3 | 11.3 | 13.5 | 11.5 | 15.0 | 11.7 |
| Lowest haemoglobin threshold, g/dL | 10.0 | 7.3 | 8.5 | 7.5 | 10.0 | 7.3 |
| No of subjects | 51 | 49 | 228 | 223 | 17 | 19 |
| Mean gestational age, weeks | 28 | 28 | 26 | 26 | 29 | 29 |
| Mean haemoglobin,† g/dL | 11.0 | 8.3 | 11.2 | 10.1 | 10.3 | 10.4 |
| Mean no of transfusions | 5.2 | 3.3‡ | 5.7 | 4.9 | 3.8 | 2.5 |
| Mean no of RBC donor exposures | 2.8 | 2.2 | 2.6 | 2.1‡ | – | – |
| Infants never transfused, % | 12 | 10 | 5 | 11‡ | – | – |
| Died, % | 2 | 4 | 18 | 19 | 6 | 11 |
*Thresholds varied with postnatal age and/or respiratory support; haematocrit thresholds converted to haemoglobin levels by dividing by 3.
†Mean haemoglobin levels at age 6 weeks in Iowa trial, at age 4 weeks in PINT trial and at day 30 in Taiwan trial.
‡Statistically significant difference, higher vs lower, p<0.05.