Kidney · LIVE

IDMS MDRD eGFR

Compute IDMS-traceable 4-variable MDRD eGFR in mL/min/1.73m2 from standardized creatinine, adult age, sex, and caller-assigned Black as used in Levey 2006.

LIVE $0.005 USDC GET /api/calc/mdrd

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

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

What it computes

Compute IDMS-traceable 4-variable MDRD eGFR in mL/min/1.73m2 from standardized creatinine, adult age, sex, and caller-assigned Black as used in Levey 2006.

When to use

When an agent must apply the published IDMS 4-variable MDRD equation rather than invent kidney function, including the Levey 2006 Black coefficient as assigned by the caller. magent does not assign race.

When not to use

• IDMS-traceable 4-variable MDRD (Levey 2006). Not the 1999 conventional 186 equation. Not CKD-EPI 2021 (egfr).
• black is caller-assigned as used in Levey 2006; magent does not assign race.
• Adults only (age 18-120). Not a pediatric equation.
• Not a treatment or dosing recommendation and not a medical device.

Formula

egfr = 175 * scr_mg_dl ** -1.154 * age ** -0.203 * sex_factor * black_factor; sex_factor = 0.742 if female else 1.0; black_factor = 1.212 if black else 1.0; IDMS-traceable 4-variable MDRD; GFR mL/min/1.73m2; Scr mg/dL

Citation

Title

Using Standardized Serum Creatinine Values in the Modification of Diet in Renal Disease Study Equation for Estimating Glomerular Filtration Rate

Authors

Levey AS, Coresh J, Greene T, Stevens LA, Zhang YL, Hendriksen S, Kusek JW, Van Lente F

Source

Ann Intern Med. 2006;145(4):247-254

DOI

10.7326/0003-4819-145-4-200608150-00004

Worked example

Also searched as

• MDRD eGFR
• IDMS MDRD
• 4-variable MDRD
• Levey 2006 GFR
• Modification of Diet in Renal Disease

Try

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

/api/calc/mdrd?creatinine_mg_dl=1.1&age=65&sex=female&black=false

Full URL: https://api.magentlab.com/api/calc/mdrd?creatinine_mg_dl=1.1&age=65&sex=female&black=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/mdrd?creatinine_mg_dl=1.1&age=65&sex=female&black=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/mdrd 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": [
    {
      "age": "65",
      "black": "false",
      "creatinine_mg_dl": "1.1",
      "sex": "female"
    },
    {
      "age": "65",
      "black": "false",
      "creatinine_mg_dl": "1.1",
      "sex": "female"
    }
  ]
}

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/mdrd",
  "items": [
    {
      "black": false,
      "units": "mL/min/1.73m2",
      "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": "Levey AS, Coresh J, Greene T, Stevens LA, Zhang YL, Hendriksen S, Kusek JW, Van Lente F",
        "doi": "10.7326/0003-4819-145-4-200608150-00004",
        "id": "levey-2006-mdrd",
        "pmid": "16908729",
        "source": "Ann Intern Med. 2006;145(4):247-254",
        "title": "Using Standardized Serum Creatinine Values in the Modification of Diet in Renal Disease Study Equation for Estimating Glomerular Filtration Rate"
      },
      "formula": "mdrd_idms_4var",
      "formula_expression": "egfr = 175 * scr_mg_dl ** -1.154 * age ** -0.203 * sex_factor * black_factor; sex_factor = 0.742 if female else 1.0; black_factor = 1.212 if black else 1.0; IDMS-traceable 4-variable MDRD; GFR mL/min/1.73m2; Scr mg/dL",
      "age_years": 65,
      "creatinine_mg_dl": 1.1,
      "sex": "female",
      "egfr_ml_min_1_73m2": 49.8
    },
    {
      "black": false,
      "units": "mL/min/1.73m2",
      "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": "Levey AS, Coresh J, Greene T, Stevens LA, Zhang YL, Hendriksen S, Kusek JW, Van Lente F",
        "doi": "10.7326/0003-4819-145-4-200608150-00004",
        "id": "levey-2006-mdrd",
        "pmid": "16908729",
        "source": "Ann Intern Med. 2006;145(4):247-254",
        "title": "Using Standardized Serum Creatinine Values in the Modification of Diet in Renal Disease Study Equation for Estimating Glomerular Filtration Rate"
      },
      "formula": "mdrd_idms_4var",
      "formula_expression": "egfr = 175 * scr_mg_dl ** -1.154 * age ** -0.203 * sex_factor * black_factor; sex_factor = 0.742 if female else 1.0; black_factor = 1.212 if black else 1.0; IDMS-traceable 4-variable MDRD; GFR mL/min/1.73m2; Scr mg/dL",
      "age_years": 65,
      "creatinine_mg_dl": 1.1,
      "sex": "female",
      "egfr_ml_min_1_73m2": 49.8
    }
  ]
}

Response

Example JSON

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

{
  "black": false,
  "units": "mL/min/1.73m2",
  "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": "Levey AS, Coresh J, Greene T, Stevens LA, Zhang YL, Hendriksen S, Kusek JW, Van Lente F",
    "doi": "10.7326/0003-4819-145-4-200608150-00004",
    "id": "levey-2006-mdrd",
    "pmid": "16908729",
    "source": "Ann Intern Med. 2006;145(4):247-254",
    "title": "Using Standardized Serum Creatinine Values in the Modification of Diet in Renal Disease Study Equation for Estimating Glomerular Filtration Rate"
  },
  "formula": "mdrd_idms_4var",
  "formula_expression": "egfr = 175 * scr_mg_dl ** -1.154 * age ** -0.203 * sex_factor * black_factor; sex_factor = 0.742 if female else 1.0; black_factor = 1.212 if black else 1.0; IDMS-traceable 4-variable MDRD; GFR mL/min/1.73m2; Scr mg/dL",
  "age_years": 65,
  "creatinine_mg_dl": 1.1,
  "sex": "female",
  "egfr_ml_min_1_73m2": 49.8
}

Client errors (HTTP 400)

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

Related tools

• CKD-EPI 2021 eGFR — Compute race-free CKD-EPI 2021 creatinine eGFR in mL/min/1.73m2.
• Cockcroft–Gault CrCl — Compute Cockcroft–Gault creatinine clearance in mL/min using total body weight.

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.