Produces a litigation-ready analysis of medical bills and supporting records for personal injury, medical-malpractice, workers'-compensation, and disability cases. Validates CPT/HCPCS/ICD-10 codes against documentation, applies a per-charge causation screen, runs a UCR/FAIR Health/MPFS reasonableness review, surfaces unbundling, upcoding, duplicate and phantom billing, flags letter-of-protection inflation, identifies collateral-source and lien interfaces, and outputs a memo whose every finding cites document, page, and Bates. Trigger on: medical billing analysis, medical bill audit, billing reasonableness review, UCR review, CPT/ICD code review, NCCI/unbundling/upcoding review, billed vs. paid analysis, letter of protection (LOP) analysis, collateral source review, chargemaster markup, causation chain, IME rebuttal prep, demand-package billing exhibit, mediation statement billing section, lien interface identification.
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Produces a litigation-ready analysis of medical bills and supporting records for personal injury, medical-malpractice, workers'-compensation, and disability cases. Validates CPT/HCPCS/ICD-10 codes against documentation, applies a per-charge causation screen, runs a UCR/FAIR Health/MPFS reasonableness review, surfaces unbundling, upcoding, duplicate and phantom billing, flags letter-of-protection inflation, identifies collateral-source and lien interfaces, and outputs a memo whose every finding cites document, page, and Bates. Trigger on: medical billing analysis, medical bill audit, billing reasonableness review, UCR review, CPT/ICD code review, NCCI/unbundling/upcoding review, billed vs. paid analysis, letter of protection (LOP) analysis, collateral source review, chargemaster markup, causation chain, IME rebuttal prep, demand-package billing exhibit, mediation statement billing section, lien interface identification.
A medical-billing analysis is simultaneously the spine of the damages case and a future exhibit at deposition, mediation, and trial. A defective analysis (invented UCR figures, missed unbundling, undocumented charges treated as valid, pre-existing same-body-part treatment not flagged, lien holders not identified) either understates the case or hands opposing counsel impeachment material. This skill produces a memo where every charge is reconciled, every code is checked against the chart, every finding cites document/page/Bates, every red flag carries a stable taxonomy ID, and every jurisdictional assumption is surfaced for counsel.
The skill is billing-side: it does not value the case, draft the demand, build the full chronology, or resolve liens. It hands those off to sibling skills.
Related skills
medical-record-chronology — full date-ordered treatment narrative; consume it, do not rebuild
medical-treatment-summary — narrative course of treatment
damages-calculator — valuation, multipliers, present value; this skill feeds it the billing-side line items
lien-resolution-summary — Medicare/Medicaid/ERISA/hospital liens; identify here, resolve there
Pre-incident records — same body parts, baseline function, medications
As applicable
Letters of protection — flag every LOP-billed line for RF-12 review
IME or peer-review reports
Life care plan — if future medicals at issue
Defaults if user does not respond (label every default in the output):
Analyze chronologically; carry billed and paid as separate columns
Flag treatment gaps > 30 days
Apply three-prong causation screen per charge (temporality, consistency, medical necessity)
Flag every jurisdictional rule [VERIFY]
Missing-material policy. Proceed with what's available. List missing categories in Section 4 (Open Items) of the output. Do not produce reasonableness or causation conclusions on a provider whose itemized bill is absent — name the gap and stop.
Workflow
Step 1 — Build Document Inventory & Bates-Map
Classify each document, assign a short stable doc-label, record Bates range and OCR status. Use the categories listed in references/OUTPUT-TEMPLATE.md Section 5. The doc-label carries through every citation in the memo.
Step 2 — Reconcile Billing Arithmetic
For each provider, verify: billed = paid + contractual adjustments + patient responsibility + outstanding balance. Record the per-provider reconciliation row (Section 7 of the output). Any failure to reconcile is itself a flag — identify the underlying cause (RF-04 duplicate, RF-05 phantom, an unrecorded adjustment, or a data-entry error) and record it. Do not paper over a delta; show it.
Step 3 — Validate Codes (CPT / HCPCS / ICD-10)
Per charge, check that:
The code is valid for the date of service (CPT/HCPCS year, ICD-10-CM specificity).
The code descriptor matches what the chart documents (procedure verb, anatomy, components).
The diagnosis on the claim supports the procedure billed.
Modifiers (-25, -59, X-modifiers, -26, -TC, -50, -RT/-LT, -51, -22) are used correctly.
Detailed mechanics, modifier-misuse catalog, NCCI/MUE framing, and DRG considerations: see references/CODE-VALIDATION.md. Never assert a code-text mapping from memory; cite the AMA codebook or CMS file, or label [VERIFY: billing expert].
Step 4 — Apply Causation Screen (per charge)
Three prongs, all required, applied to every billed line item:
Temporality — treatment began promptly for the complained-of body parts
Consistency — complaints documented throughout the course of care
Medical necessity — care relates to the diagnosis and the mechanism of injury
Failures get tagged "potentially contested — attorney review" in Section 7's Notes column and surface as red flags (RF-23 through RF-28 as applicable). The causation screen is the same screen used by damages-calculator Step 2 — keep terminology aligned.
Step 5 — Run Reasonableness Review
Produce a benchmark range, not a single "reasonable amount." Use FAIR Health, MPFS, state WC fee schedules, and the case's own EOB allowed amounts. Geographic adjustment (geozip/locality) matters. Letter-of-protection lines get extra scrutiny.
Methodology, source list, percentile presentation, billed-vs-paid integration, and "when to recommend a billing expert" thresholds: see references/REASONABLENESS-METHODOLOGY.md. Never quote a benchmark figure that was not actually retrieved; if no benchmark was run, say so and recommend a billing expert.
Step 6 — Flag Red Flags (taxonomy IDs)
Use the stable IDs in references/RED-FLAGS-CATALOG.md. Categories: billing integrity (RF-01–RF-10), reasonableness (RF-11–RF-14), referral patterns (RF-15–RF-17), documentation (RF-18–RF-22), causation (RF-23–RF-28), IME/peer-review (RF-29–RF-31), liens/collateral source (RF-32–RF-35).
Each row in Section 11 of the output: ID | Name | Detail | Source | Suggested Attorney Action | Severity (H/M/L). Sort H → M → L. If a finding doesn't match any ID, mark it [NEW PATTERN — review needed] rather than inventing a permanent ID.
Identify lien holders (Medicare, Medicaid, ERISA plan, hospital/provider, workers' comp, VA/Tricare), record amounts asserted and notice status, and hand off to lien-resolution-summary. Do not negotiate, reduce, or resolve. Surface the billed-vs-paid jurisdictional rule for counsel; do not pick the measure unilaterally.
Step 8 — Produce Final Report
Follow references/OUTPUT-TEMPLATE.md section by section. Run the Pre-Delivery Checks at the bottom of that file before declaring the draft complete. The privilege header, citation format ([doc-label, p. N, Bates XXXXXX]), and the [F]/[A]/[O] tagging convention are non-negotiable.
Checkpoint B: Post-Draft Alignment (Mandatory)
After delivering the draft, ask:
Additional providers or itemized bills still outstanding?
Client explanation for any treatment gap > 30 days, or for pre-existing same-body-part care?
Billed-vs-paid measure for this jurisdiction — which does counsel want presented as primary?
Specific causation disputes (IME contrary opinions) requiring deeper analysis?
If no response: recommend obtaining the missing provider's itemized bills (highest-value gap) and flag the billed-vs-paid jurisdiction question as the next decision. Proceed with the draft as authorized.
Quality Audit
Every finding cites document, page, and Bates (or is explicitly labeled unbated and listed in Open Items)
Per-provider billing arithmetic reconciled in Section 7; deltas shown, not hidden
A short reference for the agent or paralegal to surface in Section 14. Not a substitute for counsel research. Every entry tagged [VERIFY].
California — paid-only measure for past medical specials per Howell v. Hamilton Meats & Provisions, Inc., 52 Cal. 4th 541 (2011) [VERIFY current law]
Collateral-source-rule jurisdictions (e.g., New York) — billed amounts may be admissible as evidence of value; collateral payments cannot be used to reduce [VERIFY current law in jurisdiction]
Reasonable-value jurisdictions — present billed, paid, and a UCR benchmark band; let the fact-finder decide [VERIFY current law]
Medicare Secondary Payer — 42 U.S.C. § 1395y(b); Section 111 reporting; CMS conditional payment letter required before settlement when patient is a Medicare beneficiary [VERIFY current CMS process]
ERISA plan reimbursement — US Airways, Inc. v. McCutchen, 569 U.S. 88 (2013); FMC Corp. v. Holliday, 498 U.S. 52 (1990); made-whole and common-fund doctrines generally do not apply against self-funded ERISA plans [VERIFY plan language]
Hospital lien statutes — many states cap or reduce; cite the specific state statute and check perfection requirements [VERIFY statute]
No Surprises Act (federal, 2022 effective) — balance-billing protections for emergency services and out-of-network providers at in-network facilities [VERIFY current regs]
Letter of protection admissibility — many jurisdictions allow impeachment on referral source, factoring, and collection patterns; some recent appellate developments [VERIFY current law in jurisdiction]
Per diem / multiplier limits and statutory damages caps — vary by state and case type [VERIFY] (consult damages-calculator)
Anti-Hallucination Rules
Never invent CPT/HCPCS/ICD-10 codes, modifier meanings, or NCCI edit pairs
Never quote a FAIR Health percentile, MPFS rate, or hospital posted price not actually retrieved (cite URL/file/date or label "benchmark not obtained")
Never quote a causation statement that is not in the cited record
Tag every legal citation [VERIFY] unless it appears verbatim in a sibling skill in this repo
Distinguish fact ([F]), assumption ([A]), and opinion ([O]) in Sections 9–11 of the output
What This Skill Does NOT Do
Does not value the case (use damages-calculator)
Does not resolve, negotiate, or satisfy liens (use lien-resolution-summary)
Does not produce expert testimony — billing experts (CPC/CCS/CPMA) and medical experts are required for admissibility on contested issues
Does not opine on ultimate legal conclusions (liability, damages amount, causation in law)
Does not draft the demand letter, mediation statement, or trial exhibit list (use the named sibling skills)
Does not replace attorney review of the final memo
Attorney Review Required
This skill produces attorney work product. The memo derives entirely from documentation listed in its Section 2 and assumptions stated in its Section 3. Jurisdictional rules flagged [VERIFY] must be confirmed by counsel before reliance. No output of this skill may be sent outside the legal team without attorney review and approval.
