Respiratory · LIVE

DECAF score

DECAF

Sum Steer 2012 DECAF points from extended MRC dyspnoea, eosinophils, chest radiograph consolidation, arterial pH, and atrial fibrillation.

LIVE $0.005 USDC GET /api/calc/decaf

Markdown: /docs/decaf.md · Canonical: https://magentlab.com/docs/decaf

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

What it computes

Sum Steer 2012 DECAF points from extended MRC dyspnoea, eosinophils, chest radiograph consolidation, arterial pH, and atrial fibrillation.

When to use

When an agent needs the published Steer 2012 DECAF total and band and must not invent an early-discharge or escalation decision or a mortality percent.

When not to use

• Not a medical device. Not an early-discharge or escalation protocol. Bands follow Steer 2012 (0-1 / 2 / 3-6) and do not include mortality percents.
• eMRCD is the caller-assigned extended MRC grade 1-4, 5a, or 5b. magent does not interview the patient.
• Consolidation and atrial fibrillation are caller-assigned flags. magent does not interpret the chest radiograph or ECG.

Formula

DECAF = emrcd_points + eosinopenia + consolidation + acidemia + atrial_fibrillation; eMRCD 1-4 -> 0, 5a -> 1, 5b -> 2; eosinophils_10e9_l < 0.05 -> 1 (0.05 does not score); consolidation true -> 1; arterial_ph < 7.30 -> 1 (7.30 does not score); atrial_fibrillation true -> 1; bands 0-1 / 2 / 3-6; max 6

Citation

Title

The DECAF Score: predicting hospital mortality in exacerbations of chronic obstructive pulmonary disease

Authors

Steer J, Gibson J, Bourke SC

Source

Thorax. 2012;67(11):970-976

DOI

10.1136/thoraxjnl-2012-202103

Worked example

Also searched as

• DECAF score
• Steer DECAF
• COPD exacerbation DECAF
• eMRCD DECAF
• extended MRC DECAF
• dyspnoea eosinopenia consolidation
• COPD hospital mortality score

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/decaf?emrcd=1-4&eosinophils_10e9_l=0.10&consolidation=false&arterial_ph=7.40&atrial_fibrillation=false

Full URL: https://api.magentlab.com/api/calc/decaf?emrcd=1-4&eosinophils_10e9_l=0.10&consolidation=false&arterial_ph=7.40&atrial_fibrillation=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/decaf?emrcd=1-4&eosinophils_10e9_l=0.10&consolidation=false&arterial_ph=7.40&atrial_fibrillation=false"

Parameters

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.

POST /api/calc/decaf Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 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 (fixture)

{
  "items": [
    {
      "arterial_ph": "7.40",
      "atrial_fibrillation": "false",
      "consolidation": "false",
      "emrcd": "1-4",
      "eosinophils_10e9_l": "0.10"
    },
    {
      "arterial_ph": "7.40",
      "atrial_fibrillation": "false",
      "consolidation": "false",
      "emrcd": "1-4",
      "eosinophils_10e9_l": "0.10"
    }
  ]
}

Open bulk paywall →

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/decaf",
  "items": [
    {
      "components": [
        {
          "value": "1-4",
          "factor": "emrcd",
          "points": 0,
          "present": false
        },
        {
          "value": 0.1,
          "factor": "eosinopenia",
          "points": 0,
          "present": false
        },
        {
          "factor": "consolidation",
          "points": 0,
          "present": false
        },
        {
          "value": 7.4,
          "factor": "acidemia",
          "points": 0,
          "present": false
        },
        {
          "factor": "atrial_fibrillation",
          "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": "Steer J, Gibson J, Bourke SC",
        "doi": "10.1136/thoraxjnl-2012-202103",
        "id": "steer-2012",
        "pmid": "22895999",
        "source": "Thorax. 2012;67(11):970-976",
        "title": "The DECAF Score: predicting hospital mortality in exacerbations of chronic obstructive pulmonary disease"
      },
      "formula": "decaf",
      "formula_expression": "DECAF = emrcd_points + eosinopenia + consolidation + acidemia + atrial_fibrillation; eMRCD 1-4 -> 0, 5a -> 1, 5b -> 2; eosinophils_10e9_l < 0.05 -> 1 (0.05 does not score); consolidation true -> 1; arterial_ph < 7.30 -> 1 (7.30 does not score); atrial_fibrillation true -> 1; bands 0-1 / 2 / 3-6; max 6",
      "max_score": 6,
      "score": 0,
      "atrial_fibrillation": false,
      "arterial_ph": 7.4,
      "consolidation": false,
      "decaf_band": "0-1",
      "emrcd": "1-4",
      "eosinophils_10e9_l": 0.1
    },
    {
      "components": [
        {
          "value": "1-4",
          "factor": "emrcd",
          "points": 0,
          "present": false
        },
        {
          "value": 0.1,
          "factor": "eosinopenia",
          "points": 0,
          "present": false
        },
        {
          "factor": "consolidation",
          "points": 0,
          "present": false
        },
        {
          "value": 7.4,
          "factor": "acidemia",
          "points": 0,
          "present": false
        },
        {
          "factor": "atrial_fibrillation",
          "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": "Steer J, Gibson J, Bourke SC",
        "doi": "10.1136/thoraxjnl-2012-202103",
        "id": "steer-2012",
        "pmid": "22895999",
        "source": "Thorax. 2012;67(11):970-976",
        "title": "The DECAF Score: predicting hospital mortality in exacerbations of chronic obstructive pulmonary disease"
      },
      "formula": "decaf",
      "formula_expression": "DECAF = emrcd_points + eosinopenia + consolidation + acidemia + atrial_fibrillation; eMRCD 1-4 -> 0, 5a -> 1, 5b -> 2; eosinophils_10e9_l < 0.05 -> 1 (0.05 does not score); consolidation true -> 1; arterial_ph < 7.30 -> 1 (7.30 does not score); atrial_fibrillation true -> 1; bands 0-1 / 2 / 3-6; max 6",
      "max_score": 6,
      "score": 0,
      "atrial_fibrillation": false,
      "arterial_ph": 7.4,
      "consolidation": false,
      "decaf_band": "0-1",
      "emrcd": "1-4",
      "eosinophils_10e9_l": 0.1
    }
  ]
}

Response

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "components": [
    {
      "value": "1-4",
      "factor": "emrcd",
      "points": 0,
      "present": false
    },
    {
      "value": 0.1,
      "factor": "eosinopenia",
      "points": 0,
      "present": false
    },
    {
      "factor": "consolidation",
      "points": 0,
      "present": false
    },
    {
      "value": 7.4,
      "factor": "acidemia",
      "points": 0,
      "present": false
    },
    {
      "factor": "atrial_fibrillation",
      "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": "Steer J, Gibson J, Bourke SC",
    "doi": "10.1136/thoraxjnl-2012-202103",
    "id": "steer-2012",
    "pmid": "22895999",
    "source": "Thorax. 2012;67(11):970-976",
    "title": "The DECAF Score: predicting hospital mortality in exacerbations of chronic obstructive pulmonary disease"
  },
  "formula": "decaf",
  "formula_expression": "DECAF = emrcd_points + eosinopenia + consolidation + acidemia + atrial_fibrillation; eMRCD 1-4 -> 0, 5a -> 1, 5b -> 2; eosinophils_10e9_l < 0.05 -> 1 (0.05 does not score); consolidation true -> 1; arterial_ph < 7.30 -> 1 (7.30 does not score); atrial_fibrillation true -> 1; bands 0-1 / 2 / 3-6; max 6",
  "max_score": 6,
  "score": 0,
  "atrial_fibrillation": false,
  "arterial_ph": 7.4,
  "consolidation": false,
  "decaf_band": "0-1",
  "emrcd": "1-4",
  "eosinophils_10e9_l": 0.1
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

Related tools

• BODE — Sum Celli 2004 BODE points from BMI, FEV1 percent predicted, MMRC dyspnea, and 6-minute walk distance.
• GAP index — Sum Ley 2012 GAP index points from sex, age, FVC percent predicted, and DLCO percent predicted or cannot-perform.
• CURB-65 — Compute the CURB-65 community-acquired pneumonia severity score from age and discrete flags.

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.
• 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.