IQCP vs EQC: Why Equivalent Quality Control Was Replaced
IQCP replaced Equivalent Quality Control (EQC) as the CMS-approved alternative QC option on January 1, 2016. EQC came from the 2003 CLIA rules and focused on test systems with internal monitoring. IQCP uses risk assessment across all testing phases. EQC data can still support an IQCP, but no EQC system was grandfathered.
If you inherited old EQC paperwork, here's how it relates to IQCP today.
Last reviewed Oct 2026 · By Sound Lab Consultants CLIA team · General information, not legal advice.
Timeline
Based on the 2015 CDC review by Nancy Anderson in Clinical Microbiology Newsletter:
2003: revised CLIA rules reduced some QC frequencies and created EQC for systems with internal monitoring.
2005: a "QC for the Future" meeting at the CLSI Leadership Conference planted the IQCP concept.
2011: CLSI published EP23-A on QC based on risk management.
August 16, 2013: CMS issued the IQCP Survey and Certification memorandum.
January 1, 2016: IQCP fully in place, and EQC no longer accepted (also stated in the CAP's public IQCP FAQ (updated Nov 2024)).
What changed
CMS says IQCP is a total quality approach that considers the entire testing process, and that EQC is no longer acceptable (CMS IQCP Frequently Asked Questions (Aug 2016)). No EQC test system was grandfathered. EQC validation data can be part of an IQCP, but you still need PT, QC, QA and verification records to show stability at the chosen frequency.
If you still have EQC-era practices
Labs must follow default CLIA QC or implement IQCP. Reduced QC without an IQCP is cited against the QC regulation.
IQCP vs EQC checklist
☐ Find any test still on EQC-era reduced QC
☐ Move it to default QC or a new IQCP
☐ Reuse EQC data as historical evidence
☐ Add PT, QC, QA and verification data
☐ Director approval
CDC resources on CLIA
CDC's overview of the CLIA program: CDC explains that CLIA applies to every U.S. site that tests human specimens to assess health or to diagnose, prevent, or treat disease. It also explains that CDC supports the program alongside CMS and FDA.
CDC on CLIA test complexity categories: CDC explains how FDA scores tests as moderate or high complexity using seven criteria. It also notes that lab-developed or modified tests default to high complexity, and that moderate and high complexity standards differ only in personnel requirements.
CDC's free CLIA educational materials: CDC offers brochures and booklets on waived testing, PPM, and IQCP.
Frequently asked questions
When did IQCP replace EQC?
January 1, 2016.
Can I still use EQC?
No. CMS says EQC is no longer an acceptable QC option.
Were EQC systems grandfathered into IQCP?
No, per CMS.
Can EQC data be used in an IQCP?
Yes, as historical data, alongside PT, QC, QA and verification records.
What guideline is IQCP based on?
The 2015 CDC review says the CMS IQCP option incorporates a process similar to CLSI EP23-A, with more flexibility.
Official sources and further reading
Related IQCP guides
Talk to an IQCP consultant
Sound Lab Consultants helps labs nationwide build, review and maintain IQCPs from their own data and the official CMS and CDC guidance.
Sound Lab Consultants, PO Box 2135, Chandler, AZ 85244