# DAS28-ESR (Prevoo 1995) DAS28-ESR Status: LIVE Price: $0.005 USDC `GET /api/calc/das28_esr` HTML: https://magentlab.com/docs/das28-esr Markdown: https://magentlab.com/docs/das28-esr.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Compute the Prevoo 1995 28-joint DAS with ESR from caller-assigned tender and swollen 28-joint counts, ESR in mm/h, and patient general health on a 0-100 mm VAS. Returns the published score only. ## When to use When an agent already has 28-joint tender and swollen counts, ESR in mm/h, and a 0-100 mm patient global and needs the Prevoo 1995 DAS28-ESR arithmetic, not SDAI, not CDAI, not DAS28-CRP, and not later EULAR 2.6/3.2/5.1 cutoffs. ## When not to use - Not a medical device and not a rheumatoid arthritis diagnosis or a treatment order. - magent does not count joints or assay ESR. tjc28, sjc28, esr_mm_h, and gh are caller-assigned. GH is millimetres on a 0-100 VAS, not 0-10 cm CDAI/SDAI. - Prevoo 1995 publishes this 28-joint DAS and discriminates high vs low activity by rheumatologist decision. It does not publish the later EULAR 2.6 / 3.2 / 5.1 cutoffs. magent returns the score only. - Not SDAI. Not CDAI. Not DAS28-CRP. ## Formula ``` DAS28-ESR = 0.56*sqrt(tjc28) + 0.28*sqrt(sjc28) + 0.70*ln(esr_mm_h) + 0.014*gh; Prevoo 1995; TJC28 and SJC28 integers 0-28; ESR mm/h strictly >0 (typical 1-150, natural log); GH 0-100 mm VAS (not 0-10 CDAI/SDAI); magent does not count joints or assay ESR; no EULAR 2.6/3.2/5.1 cutoffs ``` ## Citation [Modified disease activity scores that include twenty-eight-joint counts. Development and validation in a prospective longitudinal study of patients with rheumatoid arthritis](https://doi.org/10.1002/art.1780380107) Prevoo ML, van 't Hof MA, Kuper HH, van Leeuwen MA, van de Putte LB, van Riel PL Arthritis Rheum. 1995;38(1):44-48 DOI: [10.1002/art.1780380107](https://doi.org/10.1002/art.1780380107) ## Worked example ### Zero joints, ESR 10 mm/h, GH 0 Given: `esr_mm_h=10, gh=0, sjc28=0, tjc28=0` 1. sqrt(tjc28) and sqrt(sjc28) are 0; 0.014*gh is 0 2. score = 0.70*ln(10) = 1.6118 ### GH 50 mm with ESR 1 mm/h isolates the 0-100 VAS term Given: `esr_mm_h=1, gh=50, sjc28=0, tjc28=0` 1. ln(1) = 0; joint sqrt terms are 0 2. score = 0.014*50 = 0.7 (GH is 0-100 mm, not 0-10 cm) ## Also searched as - DAS28-ESR - 28-joint disease activity score ESR - Prevoo DAS28 - DAS28 erythrocyte sedimentation rate - RA DAS28 ESR - modified DAS 28-joint ## Parameters - `tjc28` (integer, required): Caller-assigned tender joint count on the 28-joint set (Prevoo 1995). Integer 0-28. magent does not count joints. - `sjc28` (integer, required): Caller-assigned swollen joint count on the 28-joint set (Prevoo 1995). Integer 0-28. magent does not count joints. - `esr_mm_h` (number, required): Caller-assigned erythrocyte sedimentation rate in mm/h. Strictly >0 (typical 1-150 magent clamp). Natural log in the formula. magent does not assay ESR. - `gh` (number, required): Caller-assigned patient general health on a 0-100 mm VAS (Prevoo 1995). Number 0-100. Not 0-10 CDAI/SDAI centimetres. magent does not examine the patient. ## 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/das28_esr` 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": [ { "esr_mm_h": "10", "gh": "0", "sjc28": "0", "tjc28": "0" }, { "esr_mm_h": "10", "gh": "0", "sjc28": "0", "tjc28": "0" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/das28-esr Example 200: ```json { "count": 2, "path": "/api/calc/das28_esr", "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": "Prevoo ML, van 't Hof MA, Kuper HH, van Leeuwen MA, van de Putte LB, van Riel PL", "doi": "10.1002/art.1780380107", "id": "prevoo-1995", "pmid": "7818570", "source": "Arthritis Rheum. 1995;38(1):44-48", "title": "Modified disease activity scores that include twenty-eight-joint counts. Development and validation in a prospective longitudinal study of patients with rheumatoid arthritis" }, "formula": "das28_esr", "formula_expression": "DAS28-ESR = 0.56*sqrt(tjc28) + 0.28*sqrt(sjc28) + 0.70*ln(esr_mm_h) + 0.014*gh; Prevoo 1995; TJC28 and SJC28 integers 0-28; ESR mm/h strictly >0 (typical 1-150, natural log); GH 0-100 mm VAS (not 0-10 CDAI/SDAI); magent does not count joints or assay ESR; no EULAR 2.6/3.2/5.1 cutoffs", "score": 1.6118, "sjc28": 0, "tjc28": 0, "gh": 0.0, "esr_mm_h": 10.0 }, { "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": "Prevoo ML, van 't Hof MA, Kuper HH, van Leeuwen MA, van de Putte LB, van Riel PL", "doi": "10.1002/art.1780380107", "id": "prevoo-1995", "pmid": "7818570", "source": "Arthritis Rheum. 1995;38(1):44-48", "title": "Modified disease activity scores that include twenty-eight-joint counts. Development and validation in a prospective longitudinal study of patients with rheumatoid arthritis" }, "formula": "das28_esr", "formula_expression": "DAS28-ESR = 0.56*sqrt(tjc28) + 0.28*sqrt(sjc28) + 0.70*ln(esr_mm_h) + 0.014*gh; Prevoo 1995; TJC28 and SJC28 integers 0-28; ESR mm/h strictly >0 (typical 1-150, natural log); GH 0-100 mm VAS (not 0-10 CDAI/SDAI); magent does not count joints or assay ESR; no EULAR 2.6/3.2/5.1 cutoffs", "score": 1.6118, "sjc28": 0, "tjc28": 0, "gh": 0.0, "esr_mm_h": 10.0 } ] } ``` ## Response fields - `formula` (string): das28_esr - `formula_expression` (string): Exact expression used - `score` (number): Prevoo 1995 DAS28-ESR, 4 decimals. No EULAR 2.6/3.2/5.1 activity-state cutoffs. - `tjc28` (integer): Tender 28-joint count used - `sjc28` (integer): Swollen 28-joint count used - `esr_mm_h` (number): ESR in mm/h used - `gh` (number): Patient general health 0-100 mm VAS used - `citation` (object): Prevoo et al. Arthritis Rheum 1995 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": "Prevoo ML, van 't Hof MA, Kuper HH, van Leeuwen MA, van de Putte LB, van Riel PL", "doi": "10.1002/art.1780380107", "id": "prevoo-1995", "pmid": "7818570", "source": "Arthritis Rheum. 1995;38(1):44-48", "title": "Modified disease activity scores that include twenty-eight-joint counts. Development and validation in a prospective longitudinal study of patients with rheumatoid arthritis" }, "formula": "das28_esr", "formula_expression": "DAS28-ESR = 0.56*sqrt(tjc28) + 0.28*sqrt(sjc28) + 0.70*ln(esr_mm_h) + 0.014*gh; Prevoo 1995; TJC28 and SJC28 integers 0-28; ESR mm/h strictly >0 (typical 1-150, natural log); GH 0-100 mm VAS (not 0-10 CDAI/SDAI); magent does not count joints or assay ESR; no EULAR 2.6/3.2/5.1 cutoffs", "score": 1.6118, "sjc28": 0, "tjc28": 0, "gh": 0.0, "esr_mm_h": 10.0 } ``` ## Errors - HTTP 400 `invalid_das28_esr`: DAS28-ESR inputs must match Prevoo 1995 28-joint counts, ESR, and 0-100 general health. 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 - [CDAI-RA](https://magentlab.com/docs/cdai-ra) — Sum caller-assigned 28-joint swollen and tender counts and 0–10 cm patient and evaluator globals and return the Aletaha 2005 Clinical Disease Activity Index. Does not add CRP and does not return activity-state cutoffs. - [SDAI](https://magentlab.com/docs/sdai) — Sum caller-assigned 28-joint swollen and tender counts, 0–10 cm patient and evaluator globals, and CRP in mg/dL, and return the Aletaha 2005 SDAI with the newly proposed activity state. - [ACR/EULAR RA](https://magentlab.com/docs/acr-eular-ra) — Apply the 2010 ACR/EULAR rheumatoid arthritis classification criteria (Aletaha Table 3): require definite clinical synovitis, sum joint involvement, serology, acute-phase reactants, and symptom duration (max 10), and return whether score ≥6 or typical RA erosions classify RA. Not a diagnosis. ## 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.