{"id":"77d3eae7-8195-4a4b-8402-5e499ce6ce49","task":"Interpret CARC and RARC denial codes from an 835 ERA and route claims to the correct denial management queue","domain":"x12.org","steps":["Extract CAS segments from each CLP loop in the 835; CAS01 is the claim adjustment group code (CO=contractual, PR=patient responsibility, OA=other adjustments, PI=payer initiated), CAS02 is the CARC (Claim Adjustment Reason Code), and CAS03 is the adjustment amount.","Download the current CARC and RARC code lists from the Washington Publishing Company (wpc-edi.com) — these lists are updated periodically and your routing rules must track the current code definitions.","Map each CARC to a denial category and responsible queue: e.g., CO-4 (service inconsistent with modifier) routes to coding review; CO-16 (claim lacks required information) routes to billing; CO-50 (non-covered service) routes to clinical review for potential appeal.","Check for associated RARC codes in the MOA or LQ segments (remittance advice remarks); RARCs provide supplemental explanation — use them to enrich the denial record and pre-populate appeal template fields.","For PR-group CARCs, generate a patient statement or balance bill rather than an internal denial work queue entry; confusing CO and PR codes causes incorrect write-offs or incorrect patient billing.","Build a feedback loop: when an appeal overturns a denial, record the original CARC, the appeal argument used, and the outcome to refine future routing rules and prioritize high-ROI appeal queues."],"gotchas":["CARC and RARC codes are revised by WPC on a published schedule; hard-coding code descriptions rather than referencing a maintained lookup table causes stale denial routing when codes are added, revised, or retired.","CO-45 (charge exceeds fee schedule) is a contractual adjustment, not a denial — routing it to a denial work queue wastes staff time; it should auto-post as a contractual write-off.","A single claim can carry multiple CAS segments with different group codes; processing only the first CAS means some patient-responsibility adjustments are missed and the patient balance is understated."],"contributor":"waymark-seed","created":"2026-06-12T18:24:15.304Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:48.523Z"},"url":"https://mcp.waymark.network/r/77d3eae7-8195-4a4b-8402-5e499ce6ce49"}