# DRAGON score DRAGON Status: LIVE Price: $0.005 USDC `GET /api/calc/dragon` HTML: https://magentlab.com/docs/dragon Markdown: https://magentlab.com/docs/dragon.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Compute the Strbian 2012 DRAGON score (Dense artery / early infarct signs, prestroke mRS, Age, Glucose, Onset-to-treatment, NIHSS) for 3-month outcome after IV thrombolysis-treated ischemic stroke. ## When to use When an agent has caller-assigned admission CT flags, prestroke mRS >1, age, glucose, onset-to-treatment minutes, and NIHSS and needs the published DRAGON total and tabulated 3-month mRS percents, without inventing NIHSS, CT findings, or percents for scores 4-7. ## When not to use - Not a medical device and not a tPA, thrombolysis, or reperfusion treatment decision. - Derived in IV thrombolysis-treated anterior-circulation ischemic stroke (Strbian 2012). It was not studied in basilar artery occlusion. - The caller assigns NIHSS (0-42), prestroke modified Rankin Scale >1 as a flag (not a raw mRS integer), (hyper)dense cerebral artery sign, early infarct signs, glucose, and onset-to-treatment time. magent does not examine the patient, read CT, or compute NIHSS. - Published 3-month mRS 0-2 and mRS 5-6 percents are returned only for tabulated scores (0-1, 2, 3, 8, and 9-10). Scores 4-7 have no invented percents. ## Formula ``` DRAGON = dense_ct (hyperdense_artery 1 + early_infarct_signs 1; none 0, either 1, both 2) + prestroke_mrs_gt_1 (1 if prestroke mRS >1) + age (<65 0, 65-79 1, >=80 2) + glucose >8 mmol/L (1; 8.0 does not; mg/dL /18) + onset_to_treatment >90 min (1; 90 does not) + NIHSS (0-4 0, 5-9 1, 10-15 2, >15 3); Strbian 2012; max 10 ``` ## Citation [Predicting outcome of IV thrombolysis-treated ischemic stroke patients: the DRAGON score](https://doi.org/10.1212/WNL.0b013e318245d2a9) Strbian D, Meretoja A, Ahlhelm FJ, Pitkäniemi J, Lyrer P, Kaste M, Tatlisumak T Neurology. 2012;78(6):427-432 DOI: [10.1212/WNL.0b013e318245d2a9](https://doi.org/10.1212/WNL.0b013e318245d2a9) ## Worked example ### Age 60, NIHSS 3, no extras Given: `age=60, early_infarct_signs=false, glucose_mmol_l=6.0, hyperdense_artery=false, nihss=3, onset_to_treatment_min=60, prestroke_mrs_gt_1=false` 1. CT none 0; prestroke mRS >1 false 0; age 60 <65 → 0; glucose 6.0 mmol/L ≤8 → 0; onset 60 min ≤90 → 0; NIHSS 3 is 0-4 → 0 2. Score = 0 (max 10); 3-month mRS 0-2 96%; mRS 5-6 0% ### All items maxed Given: `age=80, early_infarct_signs=true, glucose_mmol_l=20.0, hyperdense_artery=true, nihss=42, onset_to_treatment_min=360, prestroke_mrs_gt_1=true` 1. CT both +2; prestroke mRS >1 +1; age ≥80 +2; glucose 20.0 mmol/L +1; onset 360 min +1; NIHSS 42 +3 2. Score = 10 (max 10); 3-month mRS 0-2 0%; mRS 5-6 100% ## Also searched as - DRAGON score - Strbian DRAGON - dense artery Rankin age glucose onset NIHSS - IV thrombolysis outcome score - 3-month mRS DRAGON - Strbian 2012 DRAGON - hyperdense MCA sign DRAGON - prestroke mRS DRAGON ## Parameters - `age` (integer, required): Age in years (18-120). Strbian 2012: <65 scores 0; 65-79 scores 1; ≥80 scores 2. - `nihss` (integer, required): Caller-assigned NIH Stroke Scale total (integer 0-42). 0-4 scores 0; 5-9 scores 1; 10-15 scores 2; >15 (16-42) scores 3. magent does not compute NIHSS or examine the patient. - `glucose_mmol_l` (number, optional): Baseline glucose in mmol/L (2.8-55.5). Provide this or glucose_mg_dl, not both. 1 point if >8.0; 8.0 does not score. - `glucose_mg_dl` (number, optional): Baseline glucose in mg/dL (50-1000). Converted as mmol/L = mg/dL / 18. Provide this or glucose_mmol_l, not both. >144 mg/dL scores; 144 does not. - `onset_to_treatment_min` (integer, required): Onset-to-treatment time in minutes (integer 0-360). >90 scores 1; 90 does not. magent does not clock the delay. - `hyperdense_artery` (boolean, required): (Hyper)dense cerebral artery sign on admission CT as assigned by the caller (Strbian 2012). true scores 1. Combined with early_infarct_signs: none 0, either 1, both 2. magent does not read CT. - `early_infarct_signs` (boolean, required): Early infarct signs on admission CT as assigned by the caller (Strbian 2012). true scores 1. Combined with hyperdense_artery: none 0, either 1, both 2. magent does not read CT. - `prestroke_mrs_gt_1` (boolean, required): Prestroke modified Rankin Scale >1 as assigned by the caller (Strbian 2012). true scores 1; false scores 0. Do not send a raw mRS integer. magent does not assign mRS. ## 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/dragon` 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": "60", "early_infarct_signs": "false", "glucose_mmol_l": "6.0", "hyperdense_artery": "false", "nihss": "3", "onset_to_treatment_min": "60", "prestroke_mrs_gt_1": "false" }, { "age": "60", "early_infarct_signs": "false", "glucose_mmol_l": "6.0", "hyperdense_artery": "false", "nihss": "3", "onset_to_treatment_min": "60", "prestroke_mrs_gt_1": "false" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/dragon Example 200: ```json { "count": 2, "path": "/api/calc/dragon", "items": [ { "components": [ { "factor": "hyperdense_artery", "points": 0, "present": false }, { "factor": "early_infarct_signs", "points": 0, "present": false }, { "factor": "prestroke_mrs_gt_1", "points": 0, "present": false }, { "value": 60, "factor": "age", "points": 0, "present": false }, { "value": 6.0, "factor": "glucose", "points": 0, "present": false }, { "value": 60, "factor": "onset_to_treatment", "points": 0, "present": false }, { "value": 3, "factor": "nihss", "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": "Strbian D, Meretoja A, Ahlhelm FJ, Pitkäniemi J, Lyrer P, Kaste M, Tatlisumak T", "doi": "10.1212/WNL.0b013e318245d2a9", "id": "strbian-2012-dragon", "pmid": "22311929", "source": "Neurology. 2012;78(6):427-432", "title": "Predicting outcome of IV thrombolysis-treated ischemic stroke patients: the DRAGON score" }, "formula": "dragon", "formula_expression": "DRAGON = dense_ct (hyperdense_artery 1 + early_infarct_signs 1; none 0, either 1, both 2) + prestroke_mrs_gt_1 (1 if prestroke mRS >1) + age (<65 0, 65-79 1, >=80 2) + glucose >8 mmol/L (1; 8.0 does not; mg/dL /18) + onset_to_treatment >90 min (1; 90 does not) + NIHSS (0-4 0, 5-9 1, 10-15 2, >15 3); Strbian 2012; max 10", "age_years": 60, "max_score": 10, "score": 0, "glucose_mmol_l": 6.0, "nihss": 3, "early_infarct_signs": false, "good_outcome_percent": 96, "hyperdense_artery": false, "miserable_outcome_percent": 0, "onset_to_treatment_min": 60, "prestroke_mrs_gt_1": false }, { "components": [ { "factor": "hyperdense_artery", "points": 0, "present": false }, { "factor": "early_infarct_signs", "points": 0, "present": false }, { "factor": "prestroke_mrs_gt_1", "points": 0, "present": false }, { "value": 60, "factor": "age", "points": 0, "present": false }, { "value": 6.0, "factor": "glucose", "points": 0, "present": false }, { "value": 60, "factor": "onset_to_treatment", "points": 0, "present": false }, { "value": 3, "factor": "nihss", "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": "Strbian D, Meretoja A, Ahlhelm FJ, Pitkäniemi J, Lyrer P, Kaste M, Tatlisumak T", "doi": "10.1212/WNL.0b013e318245d2a9", "id": "strbian-2012-dragon", "pmid": "22311929", "source": "Neurology. 2012;78(6):427-432", "title": "Predicting outcome of IV thrombolysis-treated ischemic stroke patients: the DRAGON score" }, "formula": "dragon", "formula_expression": "DRAGON = dense_ct (hyperdense_artery 1 + early_infarct_signs 1; none 0, either 1, both 2) + prestroke_mrs_gt_1 (1 if prestroke mRS >1) + age (<65 0, 65-79 1, >=80 2) + glucose >8 mmol/L (1; 8.0 does not; mg/dL /18) + onset_to_treatment >90 min (1; 90 does not) + NIHSS (0-4 0, 5-9 1, 10-15 2, >15 3); Strbian 2012; max 10", "age_years": 60, "max_score": 10, "score": 0, "glucose_mmol_l": 6.0, "nihss": 3, "early_infarct_signs": false, "good_outcome_percent": 96, "hyperdense_artery": false, "miserable_outcome_percent": 0, "onset_to_treatment_min": 60, "prestroke_mrs_gt_1": false } ] } ``` ## Response fields - `formula` (string): dragon - `formula_expression` (string): Exact expression used - `score` (integer): DRAGON points 0-10 - `max_score` (integer): Always 10 - `good_outcome_percent` (number): Published 3-month mRS 0-2 percent when tabulated (0-1, 2, 3, 8-10); null for scores 4-7 - `miserable_outcome_percent` (number): Published 3-month mRS 5-6 percent when tabulated (0-1, 2, 3, 8, 9-10); null for scores 4-7 - `age_years` (integer): Age used for trichotomized age points - `nihss` (integer): Caller-assigned NIHSS used for points - `glucose_mmol_l` (number): Baseline glucose in mmol/L (mg/dL inputs converted /18) - `onset_to_treatment_min` (integer): Onset-to-treatment minutes used for the >90 item - `hyperdense_artery` (boolean): Whether (hyper)dense cerebral artery sign was scored - `early_infarct_signs` (boolean): Whether early infarct signs were scored - `prestroke_mrs_gt_1` (boolean): Whether prestroke mRS >1 was scored - `components` (array): Per-item Strbian 2012 points - `citation` (object): Strbian 2012 Neurology citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "factor": "hyperdense_artery", "points": 0, "present": false }, { "factor": "early_infarct_signs", "points": 0, "present": false }, { "factor": "prestroke_mrs_gt_1", "points": 0, "present": false }, { "value": 60, "factor": "age", "points": 0, "present": false }, { "value": 6.0, "factor": "glucose", "points": 0, "present": false }, { "value": 60, "factor": "onset_to_treatment", "points": 0, "present": false }, { "value": 3, "factor": "nihss", "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": "Strbian D, Meretoja A, Ahlhelm FJ, Pitkäniemi J, Lyrer P, Kaste M, Tatlisumak T", "doi": "10.1212/WNL.0b013e318245d2a9", "id": "strbian-2012-dragon", "pmid": "22311929", "source": "Neurology. 2012;78(6):427-432", "title": "Predicting outcome of IV thrombolysis-treated ischemic stroke patients: the DRAGON score" }, "formula": "dragon", "formula_expression": "DRAGON = dense_ct (hyperdense_artery 1 + early_infarct_signs 1; none 0, either 1, both 2) + prestroke_mrs_gt_1 (1 if prestroke mRS >1) + age (<65 0, 65-79 1, >=80 2) + glucose >8 mmol/L (1; 8.0 does not; mg/dL /18) + onset_to_treatment >90 min (1; 90 does not) + NIHSS (0-4 0, 5-9 1, 10-15 2, >15 3); Strbian 2012; max 10", "age_years": 60, "max_score": 10, "score": 0, "glucose_mmol_l": 6.0, "nihss": 3, "early_infarct_signs": false, "good_outcome_percent": 96, "hyperdense_artery": false, "miserable_outcome_percent": 0, "onset_to_treatment_min": 60, "prestroke_mrs_gt_1": false } ``` ## 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_glucose`: glucose_mg_dl (50-1000) or glucose_mmol_l (2.8-55.5) is required Returned before settlement; you are not charged. - HTTP 400 `invalid_onset_to_treatment_min`: onset_to_treatment_min must be an integer from 0 to 360. 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 - [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). - [ASTRAL](https://magentlab.com/docs/astral) — Compute the Ntaios 2012 ASTRAL integer score (Age, Severity NIHSS, Time delay, Range of visual fields, Acute glucose, Level of consciousness) for 3-month mRS >2 after acute ischemic stroke. ## 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.