What this page shows
The simulator's default settings (the UK-sized preset) are run on 50 numbered seeds. Each result is set beside the matching NHSBT figure, grouped the way the National Liver Offering Scheme 96-month review (LAG(26)03, May 2026) presents them. Figures from the annual reports on liver transplantation use the last five reports (2021/22 to 2025/26): the mean of the five years is compared, with each year shown. The earlier years were affected by COVID-19, so look at the individual years as well as the mean. A last section sets the simulator against NHSBT's own simulation of the Transplant Benefit Score (LAG(21)60), with the clinical decisions switched off on both sides. The aim is to find where the simulation does not behave like the real list, and then work out why.
Status
- ✓ Consistent the gap is within what chance alone would give: 1.96 × √(seed SD² + NHSBT sampling SE²), plus a small margin (0.5 points for percentages, 5% otherwise).
- ≈ Borderline outside that band but within twice it, and the gap is small (under 5 points, or under half the NHSBT value).
- ✗ Not consistent more than twice the band, or outside it with a large gap: something in the model, or in how the figures are defined, differs.
Role of each measure
- Check not used to set the model up. These are the real test.
- Fitted a setting was tuned to match it (for example the death-risk scaling to 8% at 1 year), so agreement is expected.
- Input set directly from NHSBT data (for example registrations a year).
Settings used
Summary
Where the simulation and NHSBT differ
Not consistent first, then borderline; checks before fitted measures and inputs; largest gaps first within each. Click a measure to see its row. Working out why each one differs is the next step.
Not compared
- Survival after transplant (NLOS Tables 20–21): the simulator stops at transplant.
- Fast-track offering (20% of adult elective DBD transplants in 2025/26), paediatric, split, multi-organ and living-donor transplants: not modelled.
- Centres: the simulator has one national list, so centre-level figures (Tables D.1, D.2, Figure 11B) are not compared.
- Super-urgent outcomes: NHSBT does not publish outcomes after listing for super-urgent or ACLF patients in the same way.
Sources: NHS Blood and Transplant, National Liver Offering Scheme: ninety-six month review, LAG(26)03, May 2026; Annual Report on Liver Transplantation 2021/22 to 2025/26; Annual Report on Organ Utilisation 2025/26; National Liver Offering Scheme: updating the estimates used to calculate the Transplant Benefit Score — results, LAG(21)60, November 2021. The earlier NHSBT simulation of the first TBS (LAG(14)31d, 2014) used a different model and cohort and is not compared. Patient-group outcomes (Figures 3–6, B1–B4, C1–C4) were read from the report's charts, which have no tables, and are accurate to about half a point.