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What is Parallel Testing?

Parallel testing is a required step to validate accuracy during NCQA’s transition to digital HEDIS reporting. Learn how the process of parallel testing works and explore answers to the most commonly asked questions.

Parallel testing is a transitional step that ensures accuracy during the shift to digital HEDIS. During this phase:

  • Health plans report both traditional and digital HEDIS results for the same measurement year.
  • This step is mandatory for at least one measurement year.
  • It enables direct comparison between traditional and digital outputs, ensuring alignment and building trust in the new digital process.
  • Currently, participation in parallel testing is for only organizations that report through NCQA’s Interactive Data Submission System (IDSS). Organizations that do not submit through IDSS are not eligible and digital results cannot be used for public reporting. If you have questions about what results you may use for reporting , contact NCQA through my.ncqa.org.

See below to learn how health plans and vendors can validate digital HEDIS results using side-by-side IDSS submissions.

NCQA Parallel Testing for Digital Reporting for Measurement Year 2025 (MY 25)

Digital content customer

A health plan…
  • must have a traditional way (internal or vendor) to calculate measures.
  • must submit traditional HEDIS health plan results to IDSS for MY 25.
A vendor…
  • must be certified for HEDIS MY 25 using their traditional logic or have access to certified results for HEDIS MY 25.
  • must engage with at least one health plan client who is submitting traditional HEDIS health plan results to IDSS for MY 25.

Use the same data to run and compare traditional measure results to digital measure results using IDSS submissions, leveraging a traditional IDSS and cloned IDSS.

A health plan…
  • must have at least one complete IDSS submission (e.g., Medicare set, Accreditation set, state Medicaid set) but ideally a submission for each line of business.
  • must engage their auditor to evaluate data mapping, analyze member-level results, investigate differences, etc.
A vendor…
  • must have at least one client and ideally across all lines of business for an IDSS submission.
  • must engage client to run their data digitally and traditionally (or acquire their traditional results).
  • must engage client’s auditor to evaluate data mapping, analyze member-level results, investigate differences, etc.

Aggregate measure results, create separate IDSS XML files and submit for auditor evaluation.

  • Traditional measure results submitted to IDSS using typical process.
  • Digital measure results submitted to cloned version of IDSS. Unique URL to be provided to applicable participants.
Note: It is up to the health plan or vendor to produce IDSS XML result files.

Submit results, with auditor sign off, by established deadlines and provide analysis.

  • Traditional IDSS available March through June 2026 submission deadline.
  • Cloned IDSS available no later than end of March 2026 through October 31, 2026.
Provide final measure analysis between traditional and digital results to NCQA. Examples include: mapping implications, requested updates to the digital specifications, etc.

Frequently Asked Questions

Yes. Completion of NCQA’s parallel testing does not mandate that an organization report digitally in the immediate following year. However, NCQA recommends ongoing validation of results as digital measures, interoperability standards and associated tooling continue to evolve.

No, organizations may only submit results during the designated submission window for each measurement year.

Yes. Organizations may switch vendors for digital reporting without repeating parallel testing, provided the new vendor has successfully completed NCQA’s dQM Implementation Validation Program. NCQA recommends continued validation of digital results due to evolving standards and tooling.

Yes. Parallel testing is required regardless of whether an organization uses the same or different vendors to perform traditional and digital reporting.

Yes. Because data impacts and validation rationale may vary across organizations, parallel testing must be conducted with each customer.

No. NCQA digital measure output is in FHIR .json format at the member level. It is the responsibility of the organization or its vendor to convert these results into the IDSS XML format required for submission.

NCQA is monitoring and evaluating progressions in the standard for reporting submissions. If your organization has feedback on this format, please submit a PCS ticket to My NCQA.

Audit requirements for traditional reporting remain unchanged. For digital testing, there is no expectation that a separate end-to-end audit is conducted. Audit designations will not be assigned to digital results and a Final Audit Report will not be required. Instead, Certified HEDIS® Compliance Auditors will independently review the parallel testing results, compared with traditional results, including rates, initial populations, exclusions and numerators between traditional and digital reporting. They may also investigate data mapping and production processes contributing to discrepancies. Organizations should proactively engage their auditor to establish define review workflows.

No. NCQA does not require that traditional and digital results be exactly aligned or be within a pre-determined margin of variation. Differences are expected due to data infrastructure variability. The focus is on reviewing final results, enabling comparisons and supporting rationale to assess validity, which may differ across organizations.

Support for parallel testing will vary depending on customer needs. NCQA cannot assist with data mapping, CQL interpretation or validation of final results. However, NCQA provides guidance on digital measure specifications, implementation guides and other supporting materials and system-related (i.e., IDSS) questions for parallel testing submissions.

Support can be requested through My NCQA.

Any data elements for hybrid reporting are outside the scope of parallel testing.

In-scope measures include those from HEDIS Volume 2 and NCQA-stewarded Quality Rating System measures in the following domains:

  • Effectiveness of Care
  • Access/Availability of Care Measures
  • Utilization Measures
  • Risk Adjusted Utilization Measures
  • Measures Reported Using Electronic Clinical Data Systems

Health Plan Descriptive Information Measures

Yes, NCQA can support organizations that choose to batch their measures for parallel testing, especially when aiming to make incremental progress over time.

However, for final approval for digital reporting, all measures must undergo parallel testing.

The duration and staffing needs for parallel testing depend on several organizational factors, including but not limited to:

  • The tools and capabilities available to accurentely map FHIR data to digital measure requirements.
  • The team’s ability to interpret digital measure specifications and FHIR implementation guides, including understanding CQL and resolving conformance errors.
  • The tools and process in place to identify issues, trace root causes, and iterate quickly within data pipelines.

The ability to efficiently validate results between digital and traditional HEDIS measures.

Related Resources

Navigating the Storm of Data Quality

A Practical Guide to Getting Started With Digital Quality Measures

The Path to Digital HEDIS

The Language of Interoperability and Digital Quality Measurement

CQL Engines for Technical Teams

HEDIS Volume 2 Is Getting a Makeover!

Advancing Digital Quality: Addressing Data Challenges to Improve Performance

Introducing the First Cohort of the Bulk FHIR Quality Coalition

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