# PRE score PRE score Status: LIVE Price: $0.005 USDC `GET /api/calc/pre_score` HTML: https://magentlab.com/docs/pre-score Markdown: https://magentlab.com/docs/pre-score.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Compute the Pittsburgh Response to Endovascular therapy (PRE) score from age, caller-assigned NIHSS, and ASPECTS using PRE = age + 2×NIHSS - 10×ASPECTS (Rangaraju 2015). ## When to use When an agent needs the published Rangaraju 2015 PRE total, quartile, and recanalization-benefit stratum for large-vessel occlusion, and must not invent NIHSS or ASPECTS from a chart narrative or CT. ## When not to use - Not a medical device and not a thrombectomy recommendation. - The caller assigns the NINDS NIHSS total and ASPECTS. magent does not assign NIHSS or read CT. - Quartiles and recanalization-benefit groups are those published in Rangaraju 2015. magent does not invent outcome percents or extra cutpoints. - This tool does not recommend for or against endovascular therapy. ## Formula ``` PRE = age_years + 2 × nihss - 10 × aspects (Rangaraju 2015); integer arithmetic; no clamp on the total ``` ## Citation [Pittsburgh Response to Endovascular therapy (PRE) score: optimizing patient selection for endovascular therapy for large vessel occlusion strokes](https://doi.org/10.1136/neurintsurg-2014-011351) Rangaraju S, Aghaebrahim A, Streib C, Sun CH, Ribo M, Muchada M, Nogueira R, Frankel M, Gupta R, Jadhav A, Jovin TG J Neurointerv Surg. 2015;7(11):783-788 DOI: [10.1136/neurintsurg-2014-011351](https://doi.org/10.1136/neurintsurg-2014-011351) ## Worked example ### Age 65, NIHSS 18, ASPECTS 8 Given: `age=65, aspects=8, nihss=18` 1. PRE = 65 + 2×18 - 10×8 = 65 + 36 - 80 = 21 2. Quartile 0-24; recanalization_stratum -24_to_49 (Rangaraju 2015) ## Also searched as - PRE score - Pittsburgh Response to Endovascular therapy - Rangaraju PRE - PRE NIHSS ASPECTS - large vessel occlusion PRE - endovascular therapy PRE - ASPECTS NIHSS age PRE - Rangaraju 2015 PRE score ## Parameters - `age` (integer, required): Age in years (integer 18-120). - `nihss` (integer, required): Caller-assigned NIH Stroke Scale total (integer 0-42, NINDS total). magent does not assign NIHSS or examine the patient. - `aspects` (integer, required): Alberta Stroke Program Early CT Score (integer 0-10). magent does not read CT. ## 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/pre_score` 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": [ { "age": "65", "aspects": "8", "nihss": "18" }, { "age": "65", "aspects": "8", "nihss": "18" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/pre-score Example 200: ```json { "count": 2, "path": "/api/calc/pre_score", "items": [ { "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": "Rangaraju S, Aghaebrahim A, Streib C, Sun CH, Ribo M, Muchada M, Nogueira R, Frankel M, Gupta R, Jadhav A, Jovin TG", "doi": "10.1136/neurintsurg-2014-011351", "id": "rangaraju-2015", "pmid": "25320216", "source": "J Neurointerv Surg. 2015;7(11):783-788", "title": "Pittsburgh Response to Endovascular therapy (PRE) score: optimizing patient selection for endovascular therapy for large vessel occlusion strokes" }, "formula": "pre_score", "formula_expression": "PRE = age_years + 2 × nihss - 10 × aspects (Rangaraju 2015); integer arithmetic; no clamp on the total", "age_years": 65, "nihss": 18, "aspects": 8, "pre_quartile": "0-24", "pre_score": 21, "recanalization_stratum": "-24_to_49" }, { "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": "Rangaraju S, Aghaebrahim A, Streib C, Sun CH, Ribo M, Muchada M, Nogueira R, Frankel M, Gupta R, Jadhav A, Jovin TG", "doi": "10.1136/neurintsurg-2014-011351", "id": "rangaraju-2015", "pmid": "25320216", "source": "J Neurointerv Surg. 2015;7(11):783-788", "title": "Pittsburgh Response to Endovascular therapy (PRE) score: optimizing patient selection for endovascular therapy for large vessel occlusion strokes" }, "formula": "pre_score", "formula_expression": "PRE = age_years + 2 × nihss - 10 × aspects (Rangaraju 2015); integer arithmetic; no clamp on the total", "age_years": 65, "nihss": 18, "aspects": 8, "pre_quartile": "0-24", "pre_score": 21, "recanalization_stratum": "-24_to_49" } ] } ``` ## Response fields - `formula` (string): pre_score - `formula_expression` (string): Exact expression used - `pre_score` (integer): PRE = age_years + 2 × nihss - 10 × aspects; integer; no clamp on the total - `age_years` (integer): Age in years used in PRE - `nihss` (integer): Caller-assigned NIHSS used in PRE - `aspects` (integer): Caller-assigned ASPECTS used in PRE - `pre_quartile` (string): Rangaraju 2015 PRE quartile: <0, 0-24, 25-49, or >=50 - `recanalization_stratum` (string): Rangaraju 2015 recanalization-benefit group: <-24, -24_to_49, or >=50 - `citation` (object): Rangaraju 2015 citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "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": "Rangaraju S, Aghaebrahim A, Streib C, Sun CH, Ribo M, Muchada M, Nogueira R, Frankel M, Gupta R, Jadhav A, Jovin TG", "doi": "10.1136/neurintsurg-2014-011351", "id": "rangaraju-2015", "pmid": "25320216", "source": "J Neurointerv Surg. 2015;7(11):783-788", "title": "Pittsburgh Response to Endovascular therapy (PRE) score: optimizing patient selection for endovascular therapy for large vessel occlusion strokes" }, "formula": "pre_score", "formula_expression": "PRE = age_years + 2 × nihss - 10 × aspects (Rangaraju 2015); integer arithmetic; no clamp on the total", "age_years": 65, "nihss": 18, "aspects": 8, "pre_quartile": "0-24", "pre_score": 21, "recanalization_stratum": "-24_to_49" } ``` ## Errors - HTTP 400 `invalid_age`: age must be an integer from 18 to 120 Returned before settlement; you are not charged. - HTTP 400 `invalid_nihss`: nihss must be an integer from 0 to 42. Returned before settlement; you are not charged. - HTTP 400 `invalid_aspects`: aspects must be an integer from 0 to 10. Returned before settlement; you are not charged. - HTTP 400 `invalid_pre`: PRE score needs age, nihss, and aspects (Rangaraju 2015). 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 - [NIHSS](https://magentlab.com/docs/nihss) — Sum Brott 1989 NIH stroke scale points from 15 caller-assigned examination integers, including pupillary response and plantar reflex. Weaker-limb motor arm and leg. Does not apply later total-score severity bands. - [THRIVE](https://magentlab.com/docs/thrive) — Compute the Flint 2010 THRIVE (Totaled Health Risks in Vascular Events) score from trichotomized age, trichotomized NIHSS, and the chronic disease scale (hypertension, diabetes mellitus, atrial fibrillation). - [mNIHSS](https://magentlab.com/docs/mnihss) — Sum Meyer/Lyden 2001 modified NIH stroke scale points from 11 caller-assigned NINDS-style examination integers, with left/right motor and sensory collapsed to 0-1. Does not apply total-score severity bands. ## 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.