HCPCS Modifier QZ
CRNA Service: Without Medical Direction by a Physician
Source: AMA CPT / CMS HCPCS Level II definitions. Maintained by the D3rx Clinical Billing Team.
What modifier QZ means
Modifier QZ identifies an anesthetic personally performed by a Certified Registered Nurse Anesthetist (CRNA) — or other qualified non-physician anesthetist — WITHOUT medical direction by a physician. The CRNA is paid at the full (100%) fee schedule amount because no directing physician shares the case. It is common in CRNA opt-out states and in practices where CRNAs work independently.
When to use it
A CRNA (or AA) furnishes the anesthesia service on their own, not under a physician's medical direction — for example, a CRNA solely managing the anesthetic in a facility where no anesthesiologist directs the case.
Documentation checklist
The record should support every item below before you append modifier QZ.
- That a CRNA/qualified non-physician anesthetist personally performed the anesthesia
- That no physician medically directed the case (no concurrent QK/QY on a physician line)
- The anesthesia record and total anesthesia time/units
- State/practice authority for non-medically-directed CRNA practice where relevant
Do NOT use modifier QZ when
- A physician medically directed the case meeting the seven steps — the CRNA uses QX (with the physician's QK or QY) instead
- The anesthesiologist personally performed the case — use AA
- The service was monitored anesthesia care only — still report the MAC modifier QS alongside the provider modifier
Common denial reasons
- QZ billed when the documentation shows a physician actually medically directed the case (should be QX + QK/QY)
- Concurrency or supervision facts that contradict 'without medical direction'
- Missing or inconsistent anesthesia time/units supporting the claim
How to appeal a modifier QZ denial
If denied, submit the anesthesia record showing the CRNA personally performed the case and that no physician medically directed it (no concurrent QK/QY). Confirm the total anesthesia time/units reconcile, and reference state/opt-out authority for non-medically-directed CRNA practice where the payer questions it.
Payer notes
QZ pays the CRNA the full fee schedule amount (no split), unlike the medically-directed QX (paired with QK/QY). Whether a physician must supervise CRNAs is governed by state law and the federal opt-out; QZ asserts no medical direction, which is an OIG/audit focus — the record must genuinely support independence.
Related & commonly confused modifiers
Where modifier QZ is used
- Anesthesia services (00100-01999)
- CRNA-performed anesthesia in opt-out states
- Pain-management anesthesia furnished by a CRNA
Got a denial citing modifier QZ?
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Medical billing disclaimer
Modifier definitions follow standard AMA CPT and CMS HCPCS Level II guidance and are for educational reference. Payer policies, billing formats, and coverage rules vary and change. Always verify the current rule with the specific payer before submitting. D3rx is not responsible for claim outcomes.