GI · LIVE
Glasgow-Blatchford score
Compute the Blatchford 2000 Glasgow-Blatchford score from urea, haemoglobin, systolic BP, heart rate, and four clinical flags.
Markdown: /docs/glasgow-blatchford.md · Canonical: https://magentlab.com/docs/glasgow-blatchford
Not a medical device. Not a diagnosis, dose, or listing recommendation.
What it computes
Compute the Blatchford 2000 Glasgow-Blatchford score from urea, haemoglobin, systolic BP, heart rate, and four clinical flags.
When to use
When an agent needs the Blatchford 2000 Glasgow-Blatchford arithmetic for upper-gastrointestinal haemorrhage and must not invent Rockall, AIMS65, or extra GBS risk bands.
When not to use
- Not a diagnosis of the cause or severity of bleeding.
- Not Rockall (full or pre-endoscopy) and not AIMS65.
- Score 0 is the published low-risk screen for needing treatment; magent does not invent other GBS bands.
- Urea may be mmol/L or BUN mg/dL (÷ 2.8); haemoglobin may be g/L or g/dL (× 10). Points use unrounded converted SI values.
- Adults as in Blatchford 2000. The caller assigns findings; magent does not examine the patient.
Formula
GBS = urea_mmol_l table + haemoglobin_g_l table (sex-specific) + systolic_mm_hg table + (heart_rate_bpm >= 100) + melena + 2*syncope + 2*hepatic_disease + 2*cardiac_failure; max 23; score 0 low, else not_low
Citation
- Authors
- Blatchford O, Murray WR, Blatchford M
- Source
- Lancet. 2000;356(9238):1318-1321
Worked example
All items absent (score 0, low)
Given:
cardiac_failure=falseheart_rate_bpm=80hemoglobin_g_l=140hepatic_disease=falsemelena=falsesex=malesyncope=falsesystolic_mm_hg=120urea_mmol_l=5.0
- Urea 5.0 mmol/L < 6.5 → 0; male Hb 140 g/L ≥ 130 → 0; SBP 120 ≥ 110 → 0; HR 80 is not ≥100 → 0
- Melena, syncope, hepatic disease, and cardiac failure all false
- Score = 0 (max 23); gbs_risk low
Urea 25.0 mmol/L scores 6 (not_low)
Given:
cardiac_failure=falseheart_rate_bpm=80hemoglobin_g_l=140hepatic_disease=falsemelena=falsesex=malesyncope=falsesystolic_mm_hg=120urea_mmol_l=25.0
- Urea 25.0 mmol/L ≥ 25.0 → 6; remaining items absent
- Score = 6 (max 23); gbs_risk not_low
Also searched as
- Glasgow-Blatchford score
- GBS
- Blatchford score
- upper GI bleed score
- UGIB risk score
- Glasgow Blatchford
Try
Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.
Full URL: https://api.magentlab.com/api/calc/glasgow_blatchford?sex=male&urea_mmol_l=5.0&hemoglobin_g_l=140&systolic_mm_hg=120&heart_rate_bpm=80&melena=false&syncope=false&hepatic_disease=false&cardiac_failure=false
Call
Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params
return HTTP 400 before any quote or charge.
curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/glasgow_blatchford?sex=male&urea_mmol_l=5.0&hemoglobin_g_l=140&systolic_mm_hg=120&heart_rate_bpm=80&melena=false&syncope=false&hepatic_disease=false&cardiac_failure=false"
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
sex |
string | required | Sex (female or male). Haemoglobin points use the Blatchford 2000 sex-specific table. |
urea_mmol_l |
number | optional | Blood urea in mmol/L (1-50). Provide this or bun_mg_dl, not both. <6.5 scores 0; 6.5–7.9 scores 2; 8.0–9.9 scores 3; 10.0–24.9 scores 4; ≥25.0 scores 6. |
bun_mg_dl |
number | optional | BUN in mg/dL (3-140). Converted as urea_mmol_l = bun_mg_dl / 2.8. Provide this or urea_mmol_l, not both. |
hemoglobin_g_l |
number | optional | Haemoglobin in g/L (30-220). Provide this or hemoglobin_g_dl, not both. Men: <100 → 6; 100–119 → 3; 120–129 → 1; ≥130 → 0. Women: <100 → 6; 100–119 → 1; ≥120 → 0. |
hemoglobin_g_dl |
number | optional | Haemoglobin in g/dL (3-22). Converted as hemoglobin_g_l = hemoglobin_g_dl × 10. Provide this or hemoglobin_g_l, not both. |
systolic_mm_hg |
number | required | Systolic blood pressure in mm Hg (50-250). <90 scores 3; 90–99 scores 2; 100–109 scores 1; ≥110 scores 0. |
heart_rate_bpm |
integer | required | Heart rate in beats per minute (integer 30-220). Scores 1 when ≥100; 99 does not score. |
melena |
boolean | required | Melena as assigned by the caller. true or false. 1 point if true. |
syncope |
boolean | required | Syncope as assigned by the caller. true or false. 2 points if true. |
hepatic_disease |
boolean | required | Hepatic disease as assigned by the caller. true or false. 2 points if true. |
cardiac_failure |
boolean | required | Cardiac failure as assigned by the caller. true or false. 2 points if true. |
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.
- 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 (fixture)
{
"items": [
{
"cardiac_failure": "false",
"heart_rate_bpm": "80",
"hemoglobin_g_l": "140",
"hepatic_disease": "false",
"melena": "false",
"sex": "male",
"syncope": "false",
"systolic_mm_hg": "120",
"urea_mmol_l": "5.0"
},
{
"cardiac_failure": "false",
"heart_rate_bpm": "80",
"hemoglobin_g_l": "140",
"hepatic_disease": "false",
"melena": "false",
"sex": "male",
"syncope": "false",
"systolic_mm_hg": "120",
"urea_mmol_l": "5.0"
}
]
}
Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.
Example 200 (fixture)
{
"count": 2,
"path": "/api/calc/glasgow_blatchford",
"items": [
{
"components": [
{
"value": 5.0,
"factor": "urea",
"points": 0,
"present": false
},
{
"value": 140.0,
"factor": "hemoglobin",
"points": 0,
"present": false
},
{
"value": 120.0,
"factor": "systolic",
"points": 0,
"present": false
},
{
"value": 80,
"factor": "heart_rate",
"points": 0,
"present": false
},
{
"factor": "melena",
"points": 0,
"present": false
},
{
"factor": "syncope",
"points": 0,
"present": false
},
{
"factor": "hepatic_disease",
"points": 0,
"present": false
},
{
"factor": "cardiac_failure",
"points": 0,
"present": false
}
],
"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": "Blatchford O, Murray WR, Blatchford M",
"doi": "10.1016/S0140-6736(00)02816-6",
"id": "blatchford-2000",
"source": "Lancet. 2000;356(9238):1318-1321",
"title": "A risk score to predict need for treatment for upper-gastrointestinal haemorrhage"
},
"formula": "glasgow_blatchford",
"formula_expression": "GBS = urea_mmol_l table + haemoglobin_g_l table (sex-specific) + systolic_mm_hg table + (heart_rate_bpm >= 100) + melena + 2*syncope + 2*hepatic_disease + 2*cardiac_failure; max 23; score 0 low, else not_low",
"max_score": 23,
"score": 0,
"systolic_mm_hg": 120.0,
"heart_rate_bpm": 80,
"sex": "male",
"hemoglobin_g_l": 140.0,
"urea_mmol_l": 5.0,
"gbs_risk": "low"
},
{
"components": [
{
"value": 5.0,
"factor": "urea",
"points": 0,
"present": false
},
{
"value": 140.0,
"factor": "hemoglobin",
"points": 0,
"present": false
},
{
"value": 120.0,
"factor": "systolic",
"points": 0,
"present": false
},
{
"value": 80,
"factor": "heart_rate",
"points": 0,
"present": false
},
{
"factor": "melena",
"points": 0,
"present": false
},
{
"factor": "syncope",
"points": 0,
"present": false
},
{
"factor": "hepatic_disease",
"points": 0,
"present": false
},
{
"factor": "cardiac_failure",
"points": 0,
"present": false
}
],
"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": "Blatchford O, Murray WR, Blatchford M",
"doi": "10.1016/S0140-6736(00)02816-6",
"id": "blatchford-2000",
"source": "Lancet. 2000;356(9238):1318-1321",
"title": "A risk score to predict need for treatment for upper-gastrointestinal haemorrhage"
},
"formula": "glasgow_blatchford",
"formula_expression": "GBS = urea_mmol_l table + haemoglobin_g_l table (sex-specific) + systolic_mm_hg table + (heart_rate_bpm >= 100) + melena + 2*syncope + 2*hepatic_disease + 2*cardiac_failure; max 23; score 0 low, else not_low",
"max_score": 23,
"score": 0,
"systolic_mm_hg": 120.0,
"heart_rate_bpm": 80,
"sex": "male",
"hemoglobin_g_l": 140.0,
"urea_mmol_l": 5.0,
"gbs_risk": "low"
}
]
}
Response
| Field | Type | Description |
|---|---|---|
formula |
string | glasgow_blatchford |
formula_expression |
string | Exact expression used |
score |
integer | Total points 0-23 |
max_score |
integer | Always 23 |
gbs_risk |
string | low when score is 0; not_low otherwise. Score 0 is the published low-risk screen. magent does not invent other GBS bands. |
urea_mmol_l |
number | Urea used in mmol/L (after conversion), 1 decimal |
hemoglobin_g_l |
number | Haemoglobin used in g/L (after conversion), 1 decimal |
sex |
string | female or male |
systolic_mm_hg |
number | Systolic BP used, mm Hg |
heart_rate_bpm |
integer | Heart rate used, beats per minute |
components |
array | Per-item points |
citation |
object | Blatchford 2000 citation |
disclaimer |
string | Not-a-device notice |
Example JSON
Machine form of the same example. Frozen fixture. Not a live lookup.
{
"components": [
{
"value": 5.0,
"factor": "urea",
"points": 0,
"present": false
},
{
"value": 140.0,
"factor": "hemoglobin",
"points": 0,
"present": false
},
{
"value": 120.0,
"factor": "systolic",
"points": 0,
"present": false
},
{
"value": 80,
"factor": "heart_rate",
"points": 0,
"present": false
},
{
"factor": "melena",
"points": 0,
"present": false
},
{
"factor": "syncope",
"points": 0,
"present": false
},
{
"factor": "hepatic_disease",
"points": 0,
"present": false
},
{
"factor": "cardiac_failure",
"points": 0,
"present": false
}
],
"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": "Blatchford O, Murray WR, Blatchford M",
"doi": "10.1016/S0140-6736(00)02816-6",
"id": "blatchford-2000",
"source": "Lancet. 2000;356(9238):1318-1321",
"title": "A risk score to predict need for treatment for upper-gastrointestinal haemorrhage"
},
"formula": "glasgow_blatchford",
"formula_expression": "GBS = urea_mmol_l table + haemoglobin_g_l table (sex-specific) + systolic_mm_hg table + (heart_rate_bpm >= 100) + melena + 2*syncope + 2*hepatic_disease + 2*cardiac_failure; max 23; score 0 low, else not_low",
"max_score": 23,
"score": 0,
"systolic_mm_hg": 120.0,
"heart_rate_bpm": 80,
"sex": "male",
"hemoglobin_g_l": 140.0,
"urea_mmol_l": 5.0,
"gbs_risk": "low"
}
Client errors (HTTP 400)
Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.
| HTTP | Code | When |
|---|---|---|
| 400 | invalid_urea |
urea_mmol_l (1-50) or bun_mg_dl (3-140) is required, not both. Returned before settlement; you are not charged. |
| 400 | invalid_hemoglobin |
hemoglobin_g_l (30-220) or hemoglobin_g_dl (3-22) is required, not both. Returned before settlement; you are not charged. |
| 400 | invalid_sex |
sex must be female or male Returned before settlement; you are not charged. |
| 400 | invalid_systolic_bp |
systolic_mm_hg or systolic_bp_mm_hg must be a number from 50 to 250. Returned before settlement; you are not charged. |
| 400 | invalid_heart_rate |
heart_rate_bpm must be an integer from 30 to 220 Returned before settlement; you are not charged. |
| 400 | invalid_flag |
boolean clinical flags must be true or false Returned before settlement; you are not charged. |
| 400 | invalid_items |
POST body must be a JSON object with only an items array Returned before settlement; you are not charged. |
| 400 | invalid_item_count |
items must be an array of 1 to 25 objects Returned before settlement; you are not charged. |
| 400 | invalid_item |
each items entry must be a JSON object Returned before settlement; you are not charged. |
Related tools
- AIMS65 — Compute the Saltzman 2011 AIMS65 score for in-hospital mortality in acute upper GI bleeding from albumin, INR, caller-assigned altered mental status, systolic blood pressure, and age.
- Pre-endoscopy Rockall — Compute the Rockall 1996 pre-endoscopy (admission) score from age, heart rate, systolic blood pressure, and caller-assigned comorbidity after acute upper gastrointestinal haemorrhage.
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. Unpaid valid requests return HTTP 402 with a base64
PAYMENT-REQUIRED
header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake
and shared payment errors: Payments.
Stdio MCP: /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. HTTP 402 never includes the tool JSON.
- 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.