Respiratory · LIVE

BODE index

BODE

Sum Celli 2004 BODE points from BMI, FEV1 percent predicted, MMRC dyspnea, and 6-minute walk distance.

LIVE $0.005 USDC GET /api/calc/bode

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

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

What it computes

Sum Celli 2004 BODE points from BMI, FEV1 percent predicted, MMRC dyspnea, and 6-minute walk distance.

When to use

When an agent needs the published Celli 2004 BODE total and quartile and must not invent a GOLD stage or listing decision.

When not to use

Not a GOLD COPD stage and not a transplant listing protocol. Quartiles follow Celli 2004 (0-2 / 3-4 / 5-6 / 7-10).
BMI is caller-supplied kg/m^2. magent does not compute BMI from height and weight.
MMRC is the caller-assigned modified Medical Research Council grade 0-4. magent does not interview the patient.

Formula

BODE = bmi_points + fev1_points + mmrc_points + walk_points; BMI <=21 -> 1 else 0; FEV1% >=65 -> 0, 50-64 -> 1, 36-49 -> 2, <=35 -> 3; MMRC 0-1 -> 0, 2 -> 1, 3 -> 2, 4 -> 3; 6MWD m >=350 -> 0, 250-349 -> 1, 150-249 -> 2, <=149 -> 3; quartiles 0-2 / 3-4 / 5-6 / 7-10; max 10

Citation

Title: The body-mass index, airflow obstruction, dyspnea, and exercise capacity index in chronic obstructive pulmonary disease
Authors: Celli BR, Cote CG, Marin JM, et al.
Source: N Engl J Med. 2004;350(10):1005-1012
DOI: 10.1056/NEJMoa021322

Worked example

All 0-point bands (quartile 1)

Given: bmi_kg_m2=24fev1_percent_predicted=70mmrc=0six_minute_walk_m=400

BMI 24 >21 → 0; FEV1 70% ≥65 → 0; MMRC 0 → 0; 6MWD 400 m ≥350 → 0
Score = 0; quartile 1

Maximum points (quartile 4)

Given: bmi_kg_m2=21fev1_percent_predicted=20mmrc=4six_minute_walk_m=100

BMI 21 ≤21 → 1; FEV1 20% ≤35 → 3; MMRC 4 → 3; 6MWD 100 m ≤149 → 3
Score = 10; quartile 4

Also searched as

BODE index
BODE score
Celli BODE
BMI obstruction dyspnea exercise
COPD BODE
6-minute walk BODE
MMRC BODE

Try

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

/api/calc/bode?bmi_kg_m2=24&fev1_percent_predicted=70&mmrc=0&six_minute_walk_m=400

Full URL: https://api.magentlab.com/api/calc/bode?bmi_kg_m2=24&fev1_percent_predicted=70&mmrc=0&six_minute_walk_m=400

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/bode?bmi_kg_m2=24&fev1_percent_predicted=70&mmrc=0&six_minute_walk_m=400"

Parameters

Name	Type	Required	Description
`bmi_kg_m2`	number	required	Body-mass index in kg/m^2 (10-80). Caller-supplied; magent does not compute BMI from height and weight. Celli 2004: >21 scores 0; <=21 scores 1.
`fev1_percent_predicted`	number	required	FEV1 percent predicted (10-150). Celli 2004 Table 2: >=65 scores 0; 50-64 scores 1; 36-49 scores 2; <=35 scores 3.
`mmrc`	integer	required	Modified Medical Research Council dyspnea grade as an integer 0-4 (Celli 2004). 0-1 scores 0; 2 scores 1; 3 scores 2; 4 scores 3. magent does not interview the patient.
`six_minute_walk_m`	number	required	Six-minute walk distance in meters (0-1000). Celli 2004 Table 2: >=350 scores 0; 250-349 scores 1; 150-249 scores 2; <=149 scores 3.

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/bode 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": [
    {
      "bmi_kg_m2": "24",
      "fev1_percent_predicted": "70",
      "mmrc": "0",
      "six_minute_walk_m": "400"
    },
    {
      "bmi_kg_m2": "24",
      "fev1_percent_predicted": "70",
      "mmrc": "0",
      "six_minute_walk_m": "400"
    }
  ]
}

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/bode",
  "items": [
    {
      "components": [
        {
          "value": 24.0,
          "factor": "bmi",
          "points": 0,
          "present": false
        },
        {
          "value": 70.0,
          "factor": "fev1",
          "points": 0,
          "present": false
        },
        {
          "value": 0,
          "factor": "mmrc",
          "points": 0,
          "present": false
        },
        {
          "value": 400.0,
          "factor": "six_minute_walk",
          "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": "Celli BR, Cote CG, Marin JM, et al.",
        "doi": "10.1056/NEJMoa021322",
        "id": "celli-2004",
        "pmid": "14999112",
        "source": "N Engl J Med. 2004;350(10):1005-1012",
        "title": "The body-mass index, airflow obstruction, dyspnea, and exercise capacity index in chronic obstructive pulmonary disease"
      },
      "formula": "bode",
      "formula_expression": "BODE = bmi_points + fev1_points + mmrc_points + walk_points; BMI <=21 -> 1 else 0; FEV1% >=65 -> 0, 50-64 -> 1, 36-49 -> 2, <=35 -> 3; MMRC 0-1 -> 0, 2 -> 1, 3 -> 2, 4 -> 3; 6MWD m >=350 -> 0, 250-349 -> 1, 150-249 -> 2, <=149 -> 3; quartiles 0-2 / 3-4 / 5-6 / 7-10; max 10",
      "max_score": 10,
      "score": 0,
      "bmi_kg_m2": 24.0,
      "fev1_percent_predicted": 70.0,
      "mmrc": 0,
      "quartile": 1,
      "six_minute_walk_m": 400.0
    },
    {
      "components": [
        {
          "value": 24.0,
          "factor": "bmi",
          "points": 0,
          "present": false
        },
        {
          "value": 70.0,
          "factor": "fev1",
          "points": 0,
          "present": false
        },
        {
          "value": 0,
          "factor": "mmrc",
          "points": 0,
          "present": false
        },
        {
          "value": 400.0,
          "factor": "six_minute_walk",
          "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": "Celli BR, Cote CG, Marin JM, et al.",
        "doi": "10.1056/NEJMoa021322",
        "id": "celli-2004",
        "pmid": "14999112",
        "source": "N Engl J Med. 2004;350(10):1005-1012",
        "title": "The body-mass index, airflow obstruction, dyspnea, and exercise capacity index in chronic obstructive pulmonary disease"
      },
      "formula": "bode",
      "formula_expression": "BODE = bmi_points + fev1_points + mmrc_points + walk_points; BMI <=21 -> 1 else 0; FEV1% >=65 -> 0, 50-64 -> 1, 36-49 -> 2, <=35 -> 3; MMRC 0-1 -> 0, 2 -> 1, 3 -> 2, 4 -> 3; 6MWD m >=350 -> 0, 250-349 -> 1, 150-249 -> 2, <=149 -> 3; quartiles 0-2 / 3-4 / 5-6 / 7-10; max 10",
      "max_score": 10,
      "score": 0,
      "bmi_kg_m2": 24.0,
      "fev1_percent_predicted": 70.0,
      "mmrc": 0,
      "quartile": 1,
      "six_minute_walk_m": 400.0
    }
  ]
}

Response

Field	Type	Description
`formula`	string	bode
`formula_expression`	string	Exact Celli 2004 expression
`score`	integer	BODE points 0-10
`max_score`	integer	Always 10
`quartile`	integer	Celli 2004 quartile 1 (0-2), 2 (3-4), 3 (5-6), or 4 (7-10). Not a GOLD stage.
`bmi_kg_m2`	number	Caller-supplied BMI in kg/m^2
`fev1_percent_predicted`	number	FEV1 percent predicted used
`mmrc`	integer	Caller-assigned MMRC grade 0-4
`six_minute_walk_m`	number	Six-minute walk distance in meters
`components`	array	Per-factor points for bmi, fev1, mmrc, and six_minute_walk
`citation`	object	Celli et al. NEJM 2004 citation
`disclaimer`	string	Not-a-device notice

Example JSON

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

{
  "components": [
    {
      "value": 24.0,
      "factor": "bmi",
      "points": 0,
      "present": false
    },
    {
      "value": 70.0,
      "factor": "fev1",
      "points": 0,
      "present": false
    },
    {
      "value": 0,
      "factor": "mmrc",
      "points": 0,
      "present": false
    },
    {
      "value": 400.0,
      "factor": "six_minute_walk",
      "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": "Celli BR, Cote CG, Marin JM, et al.",
    "doi": "10.1056/NEJMoa021322",
    "id": "celli-2004",
    "pmid": "14999112",
    "source": "N Engl J Med. 2004;350(10):1005-1012",
    "title": "The body-mass index, airflow obstruction, dyspnea, and exercise capacity index in chronic obstructive pulmonary disease"
  },
  "formula": "bode",
  "formula_expression": "BODE = bmi_points + fev1_points + mmrc_points + walk_points; BMI <=21 -> 1 else 0; FEV1% >=65 -> 0, 50-64 -> 1, 36-49 -> 2, <=35 -> 3; MMRC 0-1 -> 0, 2 -> 1, 3 -> 2, 4 -> 3; 6MWD m >=350 -> 0, 250-349 -> 1, 150-249 -> 2, <=149 -> 3; quartiles 0-2 / 3-4 / 5-6 / 7-10; max 10",
  "max_score": 10,
  "score": 0,
  "bmi_kg_m2": 24.0,
  "fev1_percent_predicted": 70.0,
  "mmrc": 0,
  "quartile": 1,
  "six_minute_walk_m": 400.0
}

Client errors (HTTP 400)

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

HTTP	Code	When
400	`invalid_bmi_kg_m2`	bmi_kg_m2 must be a number from 10 to 80. Returned before settlement; you are not charged.
400	`invalid_fev1_percent`	fev1_percent_predicted must be a number from 10 to 150. Returned before settlement; you are not charged.
400	`invalid_mmrc`	mmrc must be an integer from 0 to 4 (Celli 2004 MMRC). Returned before settlement; you are not charged.
400	`invalid_six_minute_walk_m`	six_minute_walk_m must be a number from 0 to 1000. 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

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PaO2/FiO2 ratio — Compute the PaO2/FiO2 ratio as arterial PO2 in mm Hg divided by inspired oxygen fraction.

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.