{"uid":"cap_w9ePEskNhIXdfwJPFyX7-","slug":"magent-das28-crp-calculator-wells-2009-dfaffe75","name":"magent DAS28-CRP Calculator (Wells 2009)","description":"Wells 2009 DAS28(CRP): 0.56*sqrt(TJC28)+0.28*sqrt(SJC28)+0.014*GH+0.36*ln(CRP+1)+0.96. CRP is mg/L, not SDAI mg/dL. GH is 0-100 mm VAS, not 0-10. The +0.96 constant is required. Remission is DAS28<2.6 as stated in that paper. magent does not count joints or assay CRP. Not DAS28-ESR, SDAI, or CDAI. Not a rheumatoid arthritis diagnosis.","url":"https://api.magentlab.com/api/calc/das28_crp","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"headers":{"type":"object","additionalProperties":{"type":"string"}},"queryParams":{"type":"object","required":["tjc28","sjc28","crp_mg_l","gh"],"properties":{"gh":{"type":"number","description":"Caller-assigned general health (patient assessment) on a 0-100 mm VAS (Wells 2009; 0=best, 100=worst). Number 0-100. Not 0-10 cm SDAI PGA. magent does not examine the patient."},"sjc28":{"type":"integer","description":"Caller-assigned swollen joint count on the 28-joint set (Wells 2009 DAS28-CRP). Integer 0-28. magent does not count joints."},"tjc28":{"type":"integer","description":"Caller-assigned tender joint count on the 28-joint set (Wells 2009 DAS28-CRP). Integer 0-28. magent does not count joints."},"crp_mg_l":{"type":"number","description":"Caller-assigned C-reactive protein in mg/L (Wells 2009; not mg/dL SDAI). Number 0-500 is a magent clamp. magent does not assay CRP."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_zSsQOWqUoJfP2kAgrIMd6","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes the DAS28-CRP disease activity score for rheumatoid arthritis monitoring using the Wells 2009 formula with tender joint count, swollen joint count, CRP in mg/L, and patient global health VAS.","exampleAgentPrompt":"Calculate the DAS28-CRP score for my RA patient who has 8 tender joints, 5 swollen joints, a CRP of 14.2 mg/L, and rated their overall health as 55 on the 0-100 scale.","exampleUseCases":[{"title":"Rheumatology clinic visit documentation","prompt":"My RA patient today has 12 tender joints, 7 swollen joints, CRP came back at 22 mg/L, and she scored her general health at 68 out of 100 — what's her DAS28-CRP score and is she in remission?"},{"title":"Monitoring treatment response over time","prompt":"Last month this patient had a DAS28-CRP of 4.1, and now her tender joints are 3, swollen joints are 2, CRP is 4.5 mg/L, and general health VAS is 30 — compute the new DAS28-CRP so I can see if the biologic is working."},{"title":"Research data pipeline scoring","prompt":"I have a cohort record: tjc28=6, sjc28=4, CRP 18 mg/L, patient global health 72 mm VAS — run the Wells 2009 DAS28-CRP formula and give me the score."}],"resultDescription":"Returns the computed DAS28-CRP composite score (a continuous number, typically 0–9+), calculated as 0.56*sqrt(TJC28)+0.28*sqrt(SJC28)+0.014*GH+0.36*ln(CRP+1)+0.96. The response indicates the numeric score and whether the patient meets the remission threshold (DAS28-CRP < 2.6 per Wells 2009). Does not return a diagnosis.","failureModes":["Missing required query parameters (tjc28, sjc28, crp_mg_l, gh) returns a validation error","Integer fields (tjc28, sjc28) provided as floats may be rejected","CRP values outside the 0–500 mg/L clamped range may be clamped or rejected","Using CRP in mg/dL instead of mg/L will silently produce an incorrect score — caller must convert units","GH provided on 0–10 cm scale instead of 0–100 mm scale will silently produce an incorrect score","Payment failure (x402) returns a 402 status requiring USDC payment before retrying"],"whenToPreferThis":"Use this endpoint when you need a programmatic, formula-exact Wells 2009 DAS28-CRP calculation (not DAS28-ESR, SDAI, or CDAI) and you already have all four inputs (TJC28, SJC28, CRP in mg/L, GH on 0–100 mm VAS) from a clinical source. Prefer this over manual calculation to avoid arithmetic errors and unit confusion. Do not use if you need ESR-based DAS28, if CRP is in mg/dL and cannot be converted, or if you need a diagnostic tool rather than a scoring tool.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T07:17:39.330Z","isFirstParty":false}