Q0 and Q1 Modifiers Use for Coverage of an Implantable Cardioverter Defibrillator (ICD)

Modifier Q0 is used for services defined as an investigational clinical service provided in clinical research study that is in an approved clinical research study. Append this modifier on a Category B Investigational Device Exemption (IDE) code along with IDE number on claim.

  • Investigational clinical services are defined as those items and services that are being investigated as an objective within the study. Investigational clinical services may include items or services that are approved, unapproved, or otherwise covered (or not covered) under Medicare.

Modifier Q1 is used for services defined as a routine clinical service provided in a clinical research study that is in an approved clinical research study.

  • This modifier must be billed in conjunction with ICD-9 diagnosis code V70.7 (examination of participant in clinical trial) or ICD-10 diagnosis code Z00.6 (examination for participant or control in clinical research program).

Routine clinical services are defined as those items and services that are covered for Medicare beneficiaries outside of the clinical research study; are used for the direct patient management within the study; and, do not meet the definition of investigational clinical services. Routine clinical services may include items or services required solely for the provision of the investigational clinical services, clinically appropriate monitoring, whether or not required by the investigational clinical service, and items or services required for the prevention, diagnosis, or treatment of research related adverse events.

Implantable Cardioverter Defibrillator (ICD)

Per the National Coverage Determination (NCD) for Implantable Automatic Defibrillators (20.4), CMS mandates that providers bill the Q0 modifier for all primary prevention diagnosis codes to ensure that claims are reported appropriately to the registry. Modifier Q0 is not required to be appended for secondary prevention or replacement indications; however it may be appended when data is submitted to a qualifying data collection system.

  • Q0 - Append this modifier on a category B IDE code (e.g. CPT® 33249- Insertion or replacement of permanent implantable defibrillator system, with transvenous lead(s), single or dual chamber) if data is submitted to an FDA-approved category B IDE clinical trial, a trial under the CMS Clinical Trial Policy, or a qualifying data collection system, including approved clinical trials and registries.
    • Modifier Q0 is only required when the ICD was implanted for primary prevention of sudden cardiac death. If the ICD procedure was performed for primary prevention, and modifier Q0 is not appended, coverage for the ICD implantation cannot be established and the service will be denied.
    • CMS has provided a list of diagnosis codes that identify non-primary prevention (secondary prevention) indications or replacement implantations. These codes can be found in the CMS Internet Only Manual (IOM), Publication 100-04, Medicare Claims Processing Manual, Chapter 32, Section 270.2
  • Q1 - Append this modifier to the covered line items provided as routine clinical services during the clinical research study (e.g. sheaths, catheters, leads, guidewires, etc.).

Approved Clinical Research Study

As previously established, if the patient receiving the ICD device is enrolled in an approved clinical research study the appropriate Q0 and Q1 modifiers should be appended. In addition to reporting these modifiers, the claim should also be billed with the following:

  • If the Q0 modifier is appended, the clinical trial registry number or IDE number must be included on the claim.
  • If the Q1 modifier is appended the following codes are also required
    • Condition code 30 (non-research services provided to all patients, including managed care enrollees, enrolled in a Qualified Clinical Trial)
    • ICD-9 diagnosis code V70.7 or ICD-10 diagnosis code Z00.6



Last Updated Dec 21 , 2022