Base case cost parameters
| Parameter | Value | SE or proportion | Distribution | Source |
| TXA administration | £30.01 | – | – | BNF36, PSSRU29, assumption |
| Inpatient stays to day-28 | ||||
| Total length of stay (days) | ||||
| TXA | 5.83 | 1.46 | Gamma | HALT-IT |
| No-TXA | 5.80 | 1.47 | Gamma | HALT-IT |
| Days in ICU | ||||
| TXA | 0.4 | 0.46 | Gamma | HALT-IT |
| No-TXA | 0.4 | 0.51 | Gamma | HALT-IT |
| Unit cost per day non-ICU | £338 | – | – | Reference costs39 |
| Unit cost per day on ICU | £1594 | – | – | Reference costs39 |
| Procedures to day 28 | ||||
| Prob endoscopy - diagnostic | ||||
| TXA | 0.8 | 4781/5953 | Beta | HALT-IT |
| No-TXA | 0.79 | 4729/5978 | Beta | HALT-IT |
| Unit cost | £665 | – | – | Reference costs39 |
| Prob endoscopy - therapeutic | ||||
| TXA | 0.43 | 2542/5953 | Beta | HALT-IT |
| No-TXA | 0.44 | 2658/5978 | Beta | HALT-IT |
| Unit cost | £777 | – | – | Reference costs39 |
| Prob surgical intervention | ||||
| TXA | 0.02 | 146/5953 | Beta | HALT-IT |
| No-TXA | 0.03 | 158/5978 | Beta | HALT-IT |
| Unit cost | £1377 | – | – | Reference costs39 |
| Prob radiological - diagnostic | ||||
| TXA | 0.29 | 1704/5953 | Beta | HALT-IT |
| No-TXA | 0.29 | 1744/5978 | Beta | HALT-IT |
| Unit cost | £4986 | – | – | Reference costs39 |
| Prob radiological - therapeutic | ||||
| TXA | 0.01 | 74/5953 | Beta | HALT-IT |
| No-TXA | 0.01 | 89/5978 | Beta | HALT-IT |
| Unit cost | £4986 | – | – | Reference costs39 |
| Transfusions | ||||
| Prob blood or red cells | ||||
| TXA | 0.67 | 3984/5951 | Beta | HALT-IT |
| No-TXA | 0.67 | 4018/5978 | Beta | HALT-IT |
| Mean units of blood or red cells | ||||
| TXA | 2.80 | 0.61 | Gamma | HALT-IT |
| No-TXA | 2.90 | 0.69 | Gamma | HALT-IT |
| Unit cost | £132 | – | – | NHS Blood and Transport40 |
| Prob fresh frozen plasma | ||||
| TXA | 0.15 | 910/5951 | Beta | HALT-IT |
| No-TXA | 0.16 | 993/5978 | Beta | HALT-IT |
| Mean units fresh frozen plasma | ||||
| TXA | 0.90 | 0.61 | Gamma | HALT-IT |
| No-TXA | 1.0 | 0.66 | Gamma | HALT-IT |
| Unit cost | £31 | – | – | NHS Blood and Transport40 |
| Prob platelets | ||||
| TXA | 0.04 | 219/5951 | Beta | HALT-IT |
| No-TXA | 0.04 | 255/5978 | Beta | HALT-IT |
| Mean units of platelets | ||||
| TXA | 0.20 | 0.23 | Gamma | HALT-IT |
| No-TXA | 0.20 | 0.26 | Gamma | HALT-IT |
| Unit cost | £192 | – | – | NHS Blood and Transport40 |
| Post discharge costs | ||||
| Year 1 | £4350 | £2175* | Gamma | Ramagopalan et al41 |
| Year 2 | £1980 | £990* | Gamma | Ramagopalan et al41 |
| Year 3 | £1938 | £969* | Gamma | Ramagopalan et al41 |
*SEs were assumed to be 50% of the mean value in the base case analysis.
ICU, intensive care unit; TXA, tranexamic acid.