I keep hearing about new modifier QQ. What is this modifier used for, and is its use mandatory?


Here’s the full description of modifier QQ: Ordering professional consulted a qualified clinical decision support mechanism (CDSM) for this service and the related data was provided to the furnishing professional. Modifier QQ will be used on Medicare claims for advanced diagnostic services when the ordering physician consulted a qualified CDSM such as the American College of Radiology’s appropriate use criteria.

The use of modifier QQ is voluntary beginning July 1, 2018 and can be added to the same claim line as the CPT® code for the diagnostic service when the furnishing professional is aware of the result of the ordering professional’s consultation with a CDSM for that patient. The modifier should be reported on both the facility and professional claim.

For more information, see MLM Matters number MM10481 at

CPT® is a registered trademark of the American Medical Association.


CPT® copyright 2021 American Medical Association (AMA). All rights reserved.

Fee schedules, relative value units, conversion factors and/or related components are not assigned by the AMA, are not part of CPT, and the AMA is not recommending their use. The AMA does not directly or indirectly practice medicine or dispense medical services. The AMA assumes no liability for data contained or not contained herein.

CPT is a registered trademark of the American Medical Association.