oncology-measure-denominator-gating

name	oncology-measure-denominator-gating
description	Produce a denominator-eligibility gate (ELIGIBLE/EXCLUDED/INSUFFICIENT_INFO) with evidence mapping before scoring oncology quality measures that include EXCLUDED or stage/setting qualifiers (advanced/metastatic, unresectable, recurrent, first-line systemic therapy).

Oncology Measure Denominator Gating (EXCLUDED-first)

Workflow

1) Inputs

• measure_question: full measure prompt, including any C1/C2 requirements and output labels
• case_evidence: chart snippets/structured fields (dx/histology, staging, intent, setting, treatments, dates)
• draft_answer (optional): if provided, ignore any concordance conclusion until denominator is gated

2) Denominator extraction (from measure text only)

Extract explicit denominator qualifiers. Do not assume guideline intent.

Capture:

• Disease context: cancer type + relevant subtype (e.g., non-squamous NSCLC)
• Stage/extent: advanced/metastatic; stage group; M0/M1; unresectable; recurrent
• Treatment setting: first-line systemic therapy, metastatic systemic therapy, palliative intent, perioperative/adjuvant/neoadjuvant
• Episode/timing: diagnosis window, start-of-therapy window, “prior to X”, etc.

Write these as a checklist of denominator_requirements.

3) Evidence check (explicit stage/setting verification)

For each denominator requirement, search case_evidence and record:

• supporting quote(s) with source/date if available, or
• not found

Prefer the most definitive sources:

• TNM + stage group (e.g., T1cN2M0, stage IIIA)
• Explicit metastatic language (e.g., metastatic, M1b, distant mets to liver)
• Explicit intent/setting (e.g., palliative, first-line systemic therapy, unresectable)

4) Hard rules (guardrails)

• Hard rule A (early-stage contradiction → EXCLUDED): If the denominator implies advanced/metastatic/systemic-therapy context, and evidence explicitly indicates non-advanced disease (e.g., stage I–III with M0 and curative/surgical/adjuvant/neoadjuvant context) → EXCLUDED.

• Hard rule B (missing denominator facts → INSUFFICIENT_INFO): If the denominator requires advanced/metastatic/systemic-therapy context and the record does not establish stage/setting → INSUFFICIENT_INFO. Do not default to CONCORDANT because testing exists.

Only after ELIGIBLE, proceed to concordance scoring (biomarker adequacy/timing, etc.).

Required output (must be produced before concordance)

Return this object:

denominator_status: ELIGIBLE | EXCLUDED | INSUFFICIENT_INFO

denominator_requirements:
  - <requirement inferred from measure text>
  - ...

evidence_map:
  - requirement: <same text as above>
    evidence:
      - "<supporting quote>"  # or [] if not found
    status: MET | NOT_FOUND | CONTRADICTS

decision: <1-2 sentences explaining the denominator determination>

next_step:
  if_EXCLUDED: "Return EXCLUDED and stop. Do not score concordance."
  if_INSUFFICIENT_INFO: "Ask for the missing denominator facts and stop."
  if_ELIGIBLE: "Proceed to concordance evaluation."

Examples

Example 1 — Stage IIIA with testing present → EXCLUDED

• Measure text (implied): advanced/metastatic systemic-therapy setting.
• Evidence: “clinical stage IIIA (T1cN2M0) adenocarcinoma”; PD-L1 and NGS ordered.
• Gate: EXCLUDED (early-stage contradiction), even though testing was done.

Example 2 — Testing present but stage/setting absent → INSUFFICIENT_INFO

• Evidence: biomarker panel resulted; no stage group, no metastatic status, no systemic-therapy context.
• Gate: INSUFFICIENT_INFO; request: stage group/TNM, M status, recurrence/unresectable status, and whether first-line systemic therapy is planned/started.

Example 3 — Stage IV metastatic → ELIGIBLE then score

• Evidence: “Stage IV metastatic non-squamous NSCLC”; first-line systemic therapy planned/started; required testing documented.
• Gate: ELIGIBLE → proceed to CONCORDANT/NONCONCORDANT based on measure specifics.