# UKELD

UKELD

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/ukeld`
HTML: https://magentlab.com/docs/ukeld
Markdown: https://magentlab.com/docs/ukeld.md

Not a medical device. Not a diagnosis, dose, or listing recommendation.

## What it computes

Compute the Barber 2011 United Kingdom end-stage liver disease (UKELD) integer from INR, creatinine, bilirubin, and sodium, with the UK elective-list 9% 1-year mortality threshold of 49.

## When to use

When an agent needs the published Barber 2011 UKELD integer and must not invent a UK listing or allocation order, apply MELD floors, or substitute MELD-Na.

## When not to use

- Not a medical device.
- Not a transplant listing or allocation order.
- Barber 2011 UKELD only. This is not MELD or MELD-Na.
- Does not apply OPTN MELD lab floors or sodium clamps (125–137). Those bounds are not in Barber 2011.
- The integer 49 cut is the UK elective-list 9% 1-year mortality threshold, not a transplant listing or allocation order.

## Formula

```
UKELD = 5.395 * ln(INR) + 1.485 * ln(creatinine_umol_l) + 3.13 * ln(bilirubin_umol_l) - 81.565 * ln(sodium_mmol_l) + 435
```

## Citation

[Elective liver transplant list mortality: development of a United Kingdom end-stage liver disease score](https://doi.org/10.1097/TP.0b013e318225db4d)
Barber K, Madden S, Allen J, Collett D, Neuberger J, Gimson A; United Kingdom Liver Transplant Selection and Allocation Working Party
Transplantation. 2011;92(4):469-476
DOI: [10.1097/TP.0b013e318225db4d](https://doi.org/10.1097/TP.0b013e318225db4d)

## Worked example

### INR 1.2, creatinine 90 µmol/L, bilirubin 40 µmol/L, sodium 135 mmol/L

Given: `bilirubin_umol_l=40, creatinine_umol_l=90, inr=1.2, sodium_mmol_l=135`

1. UKELD = 5.395*ln(1.2) + 1.485*ln(90) + 3.13*ln(40) - 81.565*ln(135) + 435
2. round to nearest integer → 54
3. 54 ≥ 49 → listing_threshold


## Also searched as

- UKELD
- United Kingdom end-stage liver disease
- UK end-stage liver disease score
- Barber UKELD
- UKELD score
- UKELD listing threshold

## Parameters

- `inr` (number, required): International normalized ratio (0.8-10). Barber 2011 does not floor INR at 1.
- `creatinine_umol_l` (number, optional): Serum creatinine in µmol/L (9-1768). Provide this or creatinine_mg_dl, not both. Barber 2011 uses µmol/L; no MELD floor.
- `creatinine_mg_dl` (number, optional): Serum creatinine in mg/dL (0.1-20). Converted as µmol/L = mg/dL × 88.42. Provide this or creatinine_umol_l, not both.
- `bilirubin_umol_l` (number, optional): Total bilirubin in µmol/L (2-684). Provide this or bilirubin_mg_dl, not both. Barber 2011 uses µmol/L; no MELD floor.
- `bilirubin_mg_dl` (number, optional): Total bilirubin in mg/dL (0.1-40). Converted as µmol/L = mg/dL × 17.1. Provide this or bilirubin_umol_l, not both.
- `sodium_mmol_l` (number, required): Serum sodium in mmol/L (110-160). Barber 2011 does not clamp sodium to 125–137.

## Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

Method: `POST /api/calc/ukeld`
Max items: 25
Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic)
Status: PREVIEW

- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
- The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
- HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
- Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
- x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request:

```json
{
  "items": [
    {
      "bilirubin_umol_l": "40",
      "creatinine_umol_l": "90",
      "inr": "1.2",
      "sodium_mmol_l": "135"
    },
    {
      "bilirubin_umol_l": "40",
      "creatinine_umol_l": "90",
      "inr": "1.2",
      "sodium_mmol_l": "135"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/ukeld

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/ukeld",
  "items": [
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Barber K, Madden S, Allen J, Collett D, Neuberger J, Gimson A; United Kingdom Liver Transplant Selection and Allocation Working Party",
        "doi": "10.1097/TP.0b013e318225db4d",
        "id": "barber-2011",
        "pmid": "21775931",
        "source": "Transplantation. 2011;92(4):469-476",
        "title": "Elective liver transplant list mortality: development of a United Kingdom end-stage liver disease score"
      },
      "formula": "ukeld",
      "formula_expression": "UKELD = 5.395 * ln(INR) + 1.485 * ln(creatinine_umol_l) + 3.13 * ln(bilirubin_umol_l) - 81.565 * ln(sodium_mmol_l) + 435",
      "inr": 1.2,
      "sodium_mmol_l": 135.0,
      "bilirubin_umol_l": 40.0,
      "creatinine_umol_l": 90.0,
      "ukeld": 54,
      "ukeld_band": "listing_threshold"
    },
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Barber K, Madden S, Allen J, Collett D, Neuberger J, Gimson A; United Kingdom Liver Transplant Selection and Allocation Working Party",
        "doi": "10.1097/TP.0b013e318225db4d",
        "id": "barber-2011",
        "pmid": "21775931",
        "source": "Transplantation. 2011;92(4):469-476",
        "title": "Elective liver transplant list mortality: development of a United Kingdom end-stage liver disease score"
      },
      "formula": "ukeld",
      "formula_expression": "UKELD = 5.395 * ln(INR) + 1.485 * ln(creatinine_umol_l) + 3.13 * ln(bilirubin_umol_l) - 81.565 * ln(sodium_mmol_l) + 435",
      "inr": 1.2,
      "sodium_mmol_l": 135.0,
      "bilirubin_umol_l": 40.0,
      "creatinine_umol_l": 90.0,
      "ukeld": 54,
      "ukeld_band": "listing_threshold"
    }
  ]
}
```

## Response fields

- `formula` (string): ukeld
- `formula_expression` (string): Exact expression used
- `inr` (number): INR used
- `creatinine_umol_l` (number): Serum creatinine used in µmol/L (after conversion)
- `bilirubin_umol_l` (number): Total bilirubin used in µmol/L (after conversion)
- `sodium_mmol_l` (number): Serum sodium used in mmol/L
- `ukeld` (integer): Barber 2011 UKELD, nearest integer. No MELD lab floors.
- `ukeld_band` (string): below_listing if UKELD < 49; listing_threshold if UKELD ≥ 49 (UK elective-list 9% 1-year mortality cut). Not a transplant listing order.
- `citation` (object): Barber 2011 citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Barber K, Madden S, Allen J, Collett D, Neuberger J, Gimson A; United Kingdom Liver Transplant Selection and Allocation Working Party",
    "doi": "10.1097/TP.0b013e318225db4d",
    "id": "barber-2011",
    "pmid": "21775931",
    "source": "Transplantation. 2011;92(4):469-476",
    "title": "Elective liver transplant list mortality: development of a United Kingdom end-stage liver disease score"
  },
  "formula": "ukeld",
  "formula_expression": "UKELD = 5.395 * ln(INR) + 1.485 * ln(creatinine_umol_l) + 3.13 * ln(bilirubin_umol_l) - 81.565 * ln(sodium_mmol_l) + 435",
  "inr": 1.2,
  "sodium_mmol_l": 135.0,
  "bilirubin_umol_l": 40.0,
  "creatinine_umol_l": 90.0,
  "ukeld": 54,
  "ukeld_band": "listing_threshold"
}
```

## Errors

- HTTP 400 `invalid_inr`: inr must be a number from 0.8 to 10 Returned before settlement; you are not charged.
- HTTP 400 `invalid_creatinine`: creatinine_mg_dl (0.1-20) or creatinine_umol_l (9-1768) is required Returned before settlement; you are not charged.
- HTTP 400 `invalid_bilirubin`: bilirubin_mg_dl (0.1-40) or bilirubin_umol_l (2-684) is required Returned before settlement; you are not charged.
- HTTP 400 `invalid_sodium`: sodium_mmol_l must be a number from 110 to 160 Returned before settlement; you are not charged.
- HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
- HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
- HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged.

Shared HTTP 402 and 503: https://magentlab.com/docs/payments

## Related tools

- [MELD-Na](https://magentlab.com/docs/meld-na) — Compute OPTN/UNOS 2016 MELD and MELD-Na from creatinine, bilirubin, INR, sodium, and dialysis.
- [Child–Pugh](https://magentlab.com/docs/child-pugh) — Compute the Child–Turcotte–Pugh cirrhosis severity score from bilirubin, albumin, INR, encephalopathy, and ascites.
- [Lille score](https://magentlab.com/docs/lille) — Compute the Louvet 2007 Lille score from age, day-0 albumin, bilirubin on day 0 and day 7, creatinine, and PT seconds or INR. formula is required.

## Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional.
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.
- offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers).

Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments

Stdio MCP (one process per host): https://magentlab.com/docs/mcp

## Guarantees

- HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged.
- exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
- HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.
