# BARD score (Harrison 2008) BARD Status: LIVE Price: $0.005 USDC `GET /api/calc/bard` HTML: https://magentlab.com/docs/bard Markdown: https://magentlab.com/docs/bard.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Sum the Harrison 2008 BARD score (BMI ≥28, AST/ALT ≥0.8, diabetes) and return low (0–1) or high (2–4). ## When to use When an agent has caller-supplied BMI, AST, ALT, and a diabetes flag for a patient already recognized as NAFLD and needs the published BARD total, not a NASH diagnosis, biopsy stage, FIB-4, APRI, or NAFLD fibrosis score. ## When not to use - Not a medical device and not a NASH diagnosis. magent does not interpret a biopsy. - BMI is caller-supplied. magent does not compute BMI from height and weight in this tool. - Harrison 2008 BARD only: BMI ≥28 (1), AST/ALT ≥0.8 (2), diabetes mellitus (1). Max 4. risk_group is the paper's 2–4 vs 0–1 split (low 0–1, high 2–4), not F0–F4 stages. - A score of 2–4 was associated with OR 17 for advanced fibrosis and NPV 96% in Harrison 2008. NPV is not a biopsy result. - Not the NAFLD fibrosis score, not FIB-4, and not APRI. ## Formula ``` BARD = 1 if BMI >= 28 + 2 if AST/ALT >= 0.8 + 1 if diabetes; Harrison 2008; max 4; risk_group low 0-1, high 2-4. Not a biopsy. Not F0-F4. ``` ## Citation [Development and validation of a simple NAFLD clinical scoring system for identifying patients without advanced disease](https://doi.org/10.1136/gut.2007.146019) Harrison SA, Oliver D, Arnold HL, Gogia S, Neuschwander-Tetri BA Gut. 2008;57(10):1441-1447 DOI: [10.1136/gut.2007.146019](https://doi.org/10.1136/gut.2007.146019) ## Worked example ### BMI 25, AST 20, ALT 40, no diabetes Given: `alt_u_l=40, ast_u_l=20, bmi=25, diabetes=false` 1. BMI 25 < 28 → 0; AAR = 20/40 = 0.5 < 0.8 → 0; diabetes false → 0 2. Score = 0 (max 4); risk_group = low ## Also searched as - BARD score - Harrison BARD - NAFLD BARD - BMI AST ALT diabetes score - BARD fibrosis - Harrison 2008 BARD - AST ALT ratio BARD - NAFLD advanced fibrosis BARD ## Parameters - `bmi` (number, required): Body-mass index in kg/m^2 (10-80). >=28 scores 1 (Harrison 2008). 27.9 scores 0. Caller-supplied; magent does not compute BMI from height and weight. - `ast_u_l` (number, required): Aspartate aminotransferase in U/L (1-10000). Used with ALT for the AAR. - `alt_u_l` (number, required): Alanine aminotransferase in U/L (1-10000). AST/ALT >= 0.8 scores 2 (Harrison 2008). 0.799 scores 0. ALT must be >0. - `diabetes` (boolean, required): Diabetes mellitus as assigned by the caller (Harrison 2008). true scores 1. magent does not diagnose diabetes. ## 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/bard` 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": [ { "alt_u_l": "40", "ast_u_l": "20", "bmi": "25", "diabetes": "false" }, { "alt_u_l": "40", "ast_u_l": "20", "bmi": "25", "diabetes": "false" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/bard Example 200: ```json { "count": 2, "path": "/api/calc/bard", "items": [ { "components": [ { "value": 25.0, "factor": "bmi_ge_28", "points": 0, "present": false }, { "value": 0.5, "factor": "ast_alt_ratio_ge_0_8", "points": 0, "present": false }, { "factor": "diabetes", "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": "Harrison SA, Oliver D, Arnold HL, Gogia S, Neuschwander-Tetri BA", "doi": "10.1136/gut.2007.146019", "id": "harrison-2008", "pmid": "18390575", "source": "Gut. 2008;57(10):1441-1447", "title": "Development and validation of a simple NAFLD clinical scoring system for identifying patients without advanced disease" }, "formula": "bard", "formula_expression": "BARD = 1 if BMI >= 28 + 2 if AST/ALT >= 0.8 + 1 if diabetes; Harrison 2008; max 4; risk_group low 0-1, high 2-4. Not a biopsy. Not F0-F4.", "max_score": 4, "score": 0, "ast_u_l": 20.0, "bmi": 25.0, "alt_u_l": 40.0, "ast_alt_ratio": 0.5, "diabetes": false, "risk_group": "low" }, { "components": [ { "value": 25.0, "factor": "bmi_ge_28", "points": 0, "present": false }, { "value": 0.5, "factor": "ast_alt_ratio_ge_0_8", "points": 0, "present": false }, { "factor": "diabetes", "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": "Harrison SA, Oliver D, Arnold HL, Gogia S, Neuschwander-Tetri BA", "doi": "10.1136/gut.2007.146019", "id": "harrison-2008", "pmid": "18390575", "source": "Gut. 2008;57(10):1441-1447", "title": "Development and validation of a simple NAFLD clinical scoring system for identifying patients without advanced disease" }, "formula": "bard", "formula_expression": "BARD = 1 if BMI >= 28 + 2 if AST/ALT >= 0.8 + 1 if diabetes; Harrison 2008; max 4; risk_group low 0-1, high 2-4. Not a biopsy. Not F0-F4.", "max_score": 4, "score": 0, "ast_u_l": 20.0, "bmi": 25.0, "alt_u_l": 40.0, "ast_alt_ratio": 0.5, "diabetes": false, "risk_group": "low" } ] } ``` ## Response fields - `formula` (string): bard - `formula_expression` (string): Exact expression used - `score` (integer): BARD points 0-4 - `max_score` (integer): Always 4 (1+2+1) - `risk_group` (string): low when score is 0-1, high when 2-4 (Harrison 2008 2-4 vs 0-1 split). Not F0-F4. Not a NASH diagnosis. magent does not interpret a biopsy. - `bmi` (number): Caller-supplied BMI in kg/m^2 - `ast_u_l` (number): AST in U/L - `alt_u_l` (number): ALT in U/L - `ast_alt_ratio` (number): AST/ALT ratio (AAR), 4 decimals - `diabetes` (boolean): Caller-assigned diabetes flag used - `components` (array): Per-factor points - `citation` (object): Harrison Gut 2008 citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "value": 25.0, "factor": "bmi_ge_28", "points": 0, "present": false }, { "value": 0.5, "factor": "ast_alt_ratio_ge_0_8", "points": 0, "present": false }, { "factor": "diabetes", "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": "Harrison SA, Oliver D, Arnold HL, Gogia S, Neuschwander-Tetri BA", "doi": "10.1136/gut.2007.146019", "id": "harrison-2008", "pmid": "18390575", "source": "Gut. 2008;57(10):1441-1447", "title": "Development and validation of a simple NAFLD clinical scoring system for identifying patients without advanced disease" }, "formula": "bard", "formula_expression": "BARD = 1 if BMI >= 28 + 2 if AST/ALT >= 0.8 + 1 if diabetes; Harrison 2008; max 4; risk_group low 0-1, high 2-4. Not a biopsy. Not F0-F4.", "max_score": 4, "score": 0, "ast_u_l": 20.0, "bmi": 25.0, "alt_u_l": 40.0, "ast_alt_ratio": 0.5, "diabetes": false, "risk_group": "low" } ``` ## Errors - HTTP 400 `invalid_bard`: bmi 10-80, ast_u_l 1-10000, and alt_u_l 1-10000 (Harrison 2008; magent clamps). Returned before settlement; you are not charged. - HTTP 400 `invalid_flag`: boolean clinical flags must be true or false 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 - [NAFLD fibrosis score](https://magentlab.com/docs/nafld-fibrosis) — Compute the Angulo 2007 NAFLD fibrosis score from age, BMI, IFG/diabetes, AST, ALT, platelets, and albumin. ## 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. 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.