Choose the scores to calculate. Tick as many as you like; you will then enter only the details those scores need, and see the result for each with its formula and reference.
About
A reference calculator for the risk scores used in the assessment and prioritisation of adults with liver disease. Each score is shown with the formula exactly as published, the caps and unit conventions applied, how it is interpreted, the calculation for the current patient, and the source reference. Everything is calculated on your own device, in the browser: nothing you enter is stored or sent anywhere.
Scores are implemented from the original publications and policy documents cited on each card. Where a score has more than one published form (for example MELD-Na), the form implemented is stated on the card. Laboratory reference limits (upper/lower limits of normal) are entered by the user because scores such as GLOBE and UK-PBC use multiples of the local limits.
For information and education. Not a substitute for clinical judgement, the NHSBT offering system or local protocols, and not for use in isolation for any diagnostic or treatment decision.
Scores included
Not included, and why
- PREsTo (Eaton et al., Hepatology 2020): a gradient-boosting model with no published equation; available only as Mayo Clinic's online calculator (rtools.mayo.edu/PRESTO_calculator).
- Updated Mayo PBC model (Murtaugh et al., Hepatology 1994): the coefficients could not be verified from the primary text; the 1989 model is implemented instead.
- iMELD and MELD-Lactate (Luca et al., Liver Transpl 2007; Sarmast et al., Hepatology 2020): not yet verified against the primary texts, so not coded.
- Online-only calculators whose coefficients are computed server-side are reproduced only where the source paper publishes the full formula. Where a formula was taken from an official calculator or policy rather than the paper itself (BAR, AFP model, Child-Pugh INR bands), the card says so.
How it is checked
The calculations are written twice: once in R, where every score is tested against the published worked examples and boundary cases, and once in the JavaScript that runs on this page. Each time the page is built, both versions score the worked examples and hundreds of random patients, and the build stops if any value or line of text differs. The version of this page was built on .
Edinburgh organ allocation research group, 2026 · allocationlab.org