{"uid":"cap_9OTt0u30aaAvUveVNTdow","slug":"parc-pediatric-appendicitis-risk-calculator-kharbanda-2018-879495d2","name":"pARC Pediatric Appendicitis Risk Calculator (Kharbanda 2018)","description":"Kharbanda 2018 Table 3 pediatric appendicitis risk calculator (pARC): logistic probability from sex, age (5-18 years), pain duration, pain with walking, migration of pain to RLQ, maximal RLQ tenderness, abdominal guarding, and ANC (x10^3/uL; 1.77*sqrt(ANC) if <14, else constant 6.62). Returns logit and estimated_probability_percent. Not a medical device, not a diagnosis, not PAS, and not Alvarado. magent does not examine the child.","url":"https://api.magentlab.com/api/calc/parc","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":["age","sex","pain_duration","pain_with_walking","pain_migration_rlq","maximal_tenderness_rlq","abdominal_guarding","anc_10e3_ul"],"properties":{"age":{"type":"integer","description":"Age in whole years from 5 to 18 (Kharbanda 2018 derivation). Age 5-7 maps to 5-7.9 y; male 8-13 and female 8-11 use the age 8-13.9 y term; male 14-18 y and female 12-18 y are the Table 3 reference."},"sex":{"enum":["female","male"],"type":"string","description":"Caller-assigned sex. Male adds 1.28. Combined with age for the Table 3 age-and-sex terms. magent does not examine the child."},"anc_10e3_ul":{"type":"number","description":"Absolute neutrophil count in x10^3/uL (0-80). Kharbanda 2018 Table 3: if ANC < 14, add 1.77*sqrt(ANC); if ANC >= 14, add 6.62 instead of the sqrt term. Required; magent does not impute ANC from WBC."},"pain_duration":{"enum":["lt_24","24_lt_48","48_96"],"type":"string","description":"Kharbanda 2018 Table 3 duration of pain as assigned by the caller: lt_24 (reference, 0), 24_lt_48 (+0.47), or 48_96 (+0.10). Derivation excluded pain beyond 96 hours. Do not send a nausea or vomiting flag."},"pain_with_walking":{"type":"boolean","description":"Caller-assigned presence of pain with walking (Kharbanda 2018 Table 3 +1.05). magent does not examine the child."},"abdominal_guarding":{"type":"boolean","description":"Caller-assigned abdominal guarding (Kharbanda 2018 Table 3 +0.67). magent does not examine the child."},"pain_migration_rlq":{"type":"boolean","description":"Caller-assigned history of migration of pain to the right-lower quadrant (Kharbanda 2018 Table 3 +0.46). magent does not examine the child."},"maximal_tenderness_rlq":{"type":"boolean","description":"Caller-assigned maximal tenderness in the right-lower quadrant (Kharbanda 2018 Table 3 +1.14). magent does not examine the child."}}}},"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_JdlPY8LoFEDjegKEwrqeY","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 pediatric Appendicitis Risk Calculator (pARC) logistic probability score from clinical variables per Kharbanda 2018 Table 3, returning the logit and estimated probability percent.","exampleAgentPrompt":"Run the pARC appendicitis risk calculation for a 12-year-old male with pain duration under 24 hours, pain with walking, pain migration to the RLQ, maximal RLQ tenderness, no abdominal guarding, and an ANC of 11.5 x10^3/uL — give me the estimated probability percent.","exampleUseCases":[{"title":"ED triage appendicitis risk scoring","prompt":"I have a 9-year-old female in the ED with suspected appendicitis — pain started 30 hours ago, she has pain with walking, migration to the RLQ, maximal tenderness in the RLQ, no abdominal guarding, and her ANC is 8.2 x10^3/uL. What does the pARC calculator give for her appendicitis probability?"},{"title":"Comparing risk before imaging decision","prompt":"Before we decide on CT for this 14-year-old male with abdominal pain, can you run the Kharbanda pARC score? Pain duration is 24 to 48 hours, he has pain with walking, no migration to RLQ, maximal RLQ tenderness present, guarding present, and ANC is 16.0 x10^3/uL."},{"title":"Low-risk pediatric appendicitis workup","prompt":"Can you calculate the pARC appendicitis probability for a 7-year-old female with pain under 24 hours, no pain with walking, no pain migration to RLQ, no maximal RLQ tenderness, no guarding, and ANC of 4.5 x10^3/uL — I want to see if she's low enough risk to observe."}],"resultDescription":"Returns a JSON object with two fields: 'logit' (the raw log-odds output of the Kharbanda 2018 Table 3 logistic model) and 'estimated_probability_percent' (the converted probability of appendicitis as a percentage, 0–100). The ANC contribution uses 1.77*sqrt(ANC) if ANC < 14, or a constant 6.62 if ANC >= 14, per the published model. Not a diagnosis, not a medical device, and not equivalent to PAS or Alvarado scoring.","failureModes":["Age outside 5–18 years range causes validation error","ANC outside 0–80 x10^3/uL range rejected","Pain duration value not matching enum (lt_24, 24_lt_48, 48_96) causes schema error","Missing any required query parameter returns 400/422 error","Pain duration beyond 96 hours not supported by derivation cohort","Payment of 0.005 USDC not provided results in 402 Payment Required"],"whenToPreferThis":"Use this endpoint when you need the specific Kharbanda 2018 Table 3 pARC logistic model — not the Pediatric Appendicitis Score (PAS) or Alvarado score. Prefer pARC when your clinical inputs include an ANC value and you are working within the 5–18 year age range. This endpoint is best suited for structured clinical decision support workflows where discrete, well-defined inputs are available and you want a validated logistic probability output rather than a categorical risk tier.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T01:21:01.546Z","isFirstParty":false}