Comparison of Positive Results With and Without Heparin
| Group | Result | With heparin | Without heparin | P |
| UltraTag RBC | Clotting | 0/15 (0%) | 2/15 (13%) | 0.48 |
| Clumping | 3/15 (20%) | 3/15 (20%) | 1.0 | |
| Control | Clotting | 0/15 (0%) | 2/15 (13%) | 0.48 |
| Clumping | 10/15 (67%) | 15/15 (100%) | 0.04 |