2021 E&M CHANGES IMPACT ON DOCUMENTATION:
  Old (pre-2021): required history, exam, and MDM documented to specific level
  New (2021+): MDM OR total time determines level (history/exam no longer drive level)
  
  What this means for documentation:
    Physicians no longer need to document extensive review of systems to hit 99215
    BUT documentation still must support medical necessity for any service billed
    MDM documentation needs: problems addressed, data reviewed/ordered, risk of treatment
    Time documentation: total time on date of service (including all non-face-to-face work)

MDM DOCUMENTATION EXAMPLES:
  STRAIGHTFORWARD (99202/99212):
    "Patient here for BP check. BP 128/82 on lisinopril. Continue current regimen."
    One self-limited problem | Minimal data | Minimal risk

  LOW COMPLEXITY (99203/99213):
    "Patient with stable hypertension and type 2 DM for routine follow-up. 
     HbA1c results reviewed (7.2%). BP controlled. Refill metformin and lisinopril."
    Two stable chronic conditions | Reviewed test result | Low risk (prescription management)

  MODERATE (99204/99214):
    "New complaint of chest pain. Ordered EKG, troponin, CBC. Reviewed prior cardiology notes.
     Risk of NSTEMI cannot be excluded. Prescribing aspirin, admit for observation."
    New undiagnosed problem with uncertain prognosis | Independent interpretation | High risk

TIME-BASED DOCUMENTATION:
  "Total time spent on this encounter including pre- and post-work: 45 minutes"
  Include: chart prep, face-to-face, ordering, documentation, care coordination
  Do NOT include: time for services billed separately (procedures, tests)

CLAIM FORM ELEMENTS (CMS-1500):
  Box 21: diagnosis codes (up to 12) — ICD-10-CM
  Box 24: service lines — date, place of service, CPT, modifiers, diagnosis pointer, charge
  Box 24J: rendering provider NPI
  Box 33: billing provider NPI

COMMON DENIAL REASONS AND FIXES:
  CO-4: Procedure inconsistent with modifier — check modifier applicability
  CO-11: Diagnosis inconsistent with procedure — verify correct dx pointer
  CO-50: Non-covered service — check patient benefits, get ABN if needed
  CO-97: Bundled into another service — check NCCI edits, add modifier if appropriate
  PR-96: Non-covered charge — patient responsibility if not covered benefit
  
  APPEALS PROCESS:
    Level 1: redetermination (original MAC) — 120 days to file
    Level 2: reconsideration (QIC — Qualified Independent Contractor) — 180 days
    Level 3: ALJ (Administrative Law Judge) hearing — 60 days
    Level 4: Medicare Appeals Council — 60 days
    Level 5: Federal District Court — 60 days (if amount meets threshold)

PRIOR AUTHORIZATION:
  Required for: high-cost procedures, elective surgery, specialty referrals
  Get before service: retroactive auth usually not accepted
  Document: auth number in billing notes
  Appeal denied auth: clinical documentation + physician letter of medical necessity