{"uid":"cap_riJAnu3rKkfJkyAdWj4LK","slug":"cioms-r-factor-calculator-b-nichou-1990-01f059da","name":"CIOMS R Factor Calculator (Bénichou 1990)","description":"CIOMS R factor from ALT, ALP, and laboratory ULNs (Bénichou 1990). R = (ALT/ALT_ULN)/(ALP/ALP_ULN), rounded to 1 decimal, then hepatocellular (R ≥ 5), cholestatic (R ≤ 2), or mixed (2 < R < 5). Deterministic published arithmetic with citation. Not a medical device, not a DILI diagnosis or RUCAM score; magent does not assay enzymes. R is the enzyme pattern only.","url":"https://api.magentlab.com/api/calc/r_factor","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":["alt_u_l","alp_u_l","alt_uln_u_l","alp_uln_u_l"],"properties":{"alp_u_l":{"type":"number","description":"Alkaline phosphatase in U/L (1-10000). Must be greater than 0."},"alt_u_l":{"type":"number","description":"Alanine aminotransferase in U/L (1-10000)."},"alp_uln_u_l":{"type":"number","description":"Laboratory ALP upper limit of normal in U/L (20-500). Required; must be greater than 0."},"alt_uln_u_l":{"type":"number","description":"Laboratory ALT upper limit of normal in U/L (5-200). Required; magent does not assume 40."}}}},"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_wa5jDY8lQyOYhbdOKHDU4","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 CIOMS R factor from ALT, ALP, and their laboratory upper limits of normal to classify drug-induced liver injury pattern as hepatocellular, cholestatic, or mixed.","exampleAgentPrompt":"Calculate the CIOMS R factor for a patient with ALT of 180 U/L (ULN 40 U/L) and ALP of 95 U/L (ULN 120 U/L) — is the liver injury pattern hepatocellular, cholestatic, or mixed?","exampleUseCases":[{"title":"Drug hepatotoxicity pattern classification","prompt":"A patient on a new medication has ALT of 250 U/L with a lab ULN of 45 U/L and ALP of 80 U/L with a lab ULN of 110 U/L — calculate the R factor and tell me if this is hepatocellular, cholestatic, or mixed injury."},{"title":"Pharmacovigilance case review","prompt":"For a suspected drug reaction report, I need the CIOMS R factor: ALT is 320 U/L, ALT ULN is 40 U/L, ALP is 210 U/L, ALP ULN is 130 U/L. What's the R value and the liver injury pattern?"},{"title":"Clinical trial safety data annotation","prompt":"I'm reviewing a safety event — ALT came back at 95 U/L against a ULN of 35 U/L, and ALP is 145 U/L against a ULN of 100 U/L. Compute the Bénichou R factor so I can label the enzyme pattern."}],"resultDescription":"Returns the computed R factor value (rounded to one decimal place) and the CIOMS pattern classification: hepatocellular (R ≥ 5), cholestatic (R ≤ 2), or mixed (2 < R < 5), based on the formula R = (ALT/ALT_ULN) / (ALP/ALP_ULN) per Bénichou 1990.","failureModes":["Missing required query parameters (alt_u_l, alp_u_l, alt_uln_u_l, alp_uln_u_l) returns a 4xx validation error","ALP or ALP ULN of 0 causes division-by-zero and is rejected (must be >0)","Values outside accepted ranges (e.g. ALT ULN outside 5–200 U/L) may be rejected with validation error","Payment not included or insufficient (x402 protocol) results in 402 Payment Required"],"whenToPreferThis":"Use this endpoint when you need a deterministic, standards-referenced CIOMS R factor calculation using lab-specific ULNs rather than assumed normal ranges. Prefer it when building pharmacovigilance pipelines, annotating DILI cases, or automating hepatotoxicity pattern classification in clinical trial safety workflows. It is not a RUCAM calculator and does not perform diagnosis — it computes the enzyme pattern ratio only.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T13:17:17.218Z","isFirstParty":false}