13.4 Regulations: Federal Government and Accrediting Agencies

13.4 Regulations: Federal Government and Accrediting Agencies

Quick Answer: Clinical IHC in the United States sits under CLIA (CMS). Most IHC that laboratories develop or modify is high complexity. FDA clearance or approval applies to the manufacturer's IVD as labeled; an LDT or a kit used off the IFU must establish performance specifications. CAP LAP is a CMS-approved accrediting agency; laboratories follow the current CAP checklists, which may lag a 2024 CAP guideline. Competency uses six procedures, at least semiannually in year one, then annually. Do not memorize unpublished CLIA fee tables.

This OpenExamPrep section is independent teaching on U.S. federal and accrediting-agency frames covering published QIHC laboratory-operations topic areas (the outline's examples include CLIA and FDA). It is not a CMS, FDA, CAP, or ASCP publication and does not claim approval or partnership.

CLIA is the federal laboratory law

The Clinical Laboratory Improvement Amendments (CLIA) are administered for CMS and implemented in 42 CFR Part 493. Any laboratory that reports patient results used in diagnosis, prevention, or treatment needs an appropriate CLIA certificate. Waived tests are not the IHC menu. IHC, immunofluorescence, and ISH performed for patient care are nonwaived. FDA-cleared commercial test systems receive a complexity score; tests developed by the laboratory or modified from the manufacturer's approved instructions default to high complexity under CLIA. That is why IHC is taught as high-complexity work for personnel, supervision, and quality-system purposes even when a pretty autostainer does the pipetting.

High complexity versus moderate complexity differs mainly in personnel qualifications. Quality-system standards for nonwaived testing still include procedure manuals, verification or establishment of performance specifications, quality control, proficiency testing or equivalent, and inspection. Do not treat "the robot is moderate complexity" as a fact because the instrument has a touch screen.

Certificate types you should recognize conceptually (without reciting unpublished dollar fees):

• Certificate of Waiver — not an IHC laboratory
• Certificate of Provider-Performed Microscopy — not an IHC menu
• Certificate of Registration — typically while a lab awaits survey
• Certificate of Compliance — CMS or state survey to CLIA
• Certificate of Accreditation — survey by a CMS-approved accreditation organization (CAP, Joint Commission, COLA, and others on the current CMS list)

This guide does not publish CLIA certificate application fees. Those amounts change. Use the current CMS CLIA fee schedule if you must budget; QIHC items test structure, not a memorized invoice.

Verification versus establishment (42 CFR 493.1253) is the operations hinge Chapter 12 already used:

• Unmodified FDA-cleared or approved test system: the laboratory verifies that it can obtain performance comparable to the manufacturer (accuracy, precision, reportable range as applicable) and that reference intervals fit the population.
• Modified FDA method, method without manufacturer specs, or laboratory-developed test: the laboratory establishes performance specifications: accuracy, precision, analytic sensitivity, analytic specificity (including interfering substances), reportable range, reference intervals as applicable, and any other characteristic required for the test.

IHC "LDT" in daily speech often means a concentrate the laboratory titered, a clone the laboratory chose, or a protocol the laboratory wrote. CAP 2024 Goldsmith published analytic-validation practice (concordance thresholds and starting sample sizes such as 10-plus-10 or 20-plus-20) is how many laboratories design that establishment work. It is not a substitute for reading 493.1253, and it is not automatically every line of the CAP checklist in force on inspection day.

CAP Laboratory Accreditation Program

The College of American Pathologists Laboratory Accreditation Program (CAP LAP) is a CMS-approved accreditation organization. A laboratory that chooses CAP and holds a CLIA Certificate of Accreditation is inspected against current CAP checklists (common plus anatomic pathology and any other applicable checklists), not against a blog, not against an old printed binder, and not against a guideline PDF taped to a fridge.

Guideline versus checklist: CAP published an updated analytic validation of immunohistochemical assays guideline (Goldsmith and coauthors, 2024). That document is evidence-based practice. Checklist requirements are the accreditation language inspectors score. A 2024 guideline recommendation may not yet match every checklist item. When they differ, the laboratory still has to satisfy the current checklist to remain accredited, and it should document how it considered the guideline. Teach both facts: know the Goldsmith numbers from Chapter 12 as published CAP practice, and know that "we printed the 2024 paper" is not a waiver from the live checklist.

CAP also publishes educational IHC FAQs that explain how the program currently treats predictive-marker proficiency testing versus alternative performance assessment. Those details change by year and by marker. A laboratory director uses the current CAP checklist and PT catalog. Do not freeze a 2025 marker list as eternal federal law. Conceptually:

• Some predictive IHC markers may require enrollment in a CAP-accepted PT program when the same laboratory stains and interprets.
• Laboratories that only stain or only interpret may be directed to alternative performance assessment instead of that PT product.
• Other predictive markers may require semiannual alternative assessment without a CAP PT product.
• Nonpredictive IHC still needs a quality plan; "no CMS-regulated PT analyte" does not mean "no quality check."

Follow the current checklist. Alternative assessment might be blinded recuts, interlaboratory exchange, or other director-approved methods—not a hallway glance at last week's tonsil.

Joint Commission, COLA, and state programs can also accredit or license. QIHC's published examples are U.S. CLIA and FDA frames; CAP is the accreditor most anatomic-pathology IHC laboratories meet in practice. If a stem names a state clinical-laboratory license, that can add requirements on top of CLIA, not instead of CLIA.

FDA: clearance, approval, and laboratory-developed tests

The Food and Drug Administration regulates in vitro diagnostic devices that manufacturers ship in interstate commerce. Words that matter:

Unmodified use: verify. Modified or LDT: establish. Predictive markers used to select therapy are still laboratory tests under CLIA even when an FDA companion diagnostic exists; if you follow the IFU on the intended specimen, you verify that system. If you apply a gastric HER2 kit to a new organ without a claim, you have left the labeled intended use.

FDA does not replace CAP concordance tables. FDA does not set OSHA formaldehyde PELs. Keep the agencies in their lanes: OSHA for chemical exposure, CMS/CLIA for laboratory certification and personnel, FDA for commercial IVD claims, CAP (if chosen) for accreditation checklists.

This section will not invent a future FDA LDT enforcement date as if it were already a QIHC fact. If policy changes, read the current FDA and CMS sources. The testable distinction on a 2026 independent study item remains cleared/approved IVD as labeled versus LDT or modified method.

Personnel competency

High-complexity testing personnel must meet CLIA qualifications in 42 CFR 493.1489 (state license if required, plus a defined education and training route: doctoral/master's/bachelor's in a laboratory science, associate-degree routes, military training, or the regulation's other listed paths, including a grandfathering provision for people already serving as high-complexity testing personnel as of December 28, 2024 who have done so continuously since). QIHC does not require you to recast the entire table from memory. It does require you to know that loading an IHC stainer that produces reportable results is testing, and that unqualified staff cannot be "just the button person" without meeting the standard.

Competency assessment is not an annual HR performance review and is not the same as proficiency testing. CMS describes six required procedures for people who perform nonwaived testing, for each test they are approved to perform:

1. Direct observation of routine test performance, including specimen handling and testing
2. Monitoring recording and reporting of results
3. Review of intermediate results or worksheets, QC, PT, and preventive-maintenance records
4. Direct observation of instrument maintenance and function checks
5. Assessment of test performance using previously analyzed specimens, internal blind samples, or external PT samples
6. Assessment of problem-solving skills

Frequency (42 CFR 493.1451): evaluate individuals who perform high-complexity testing at least semiannually during the first year they test patient specimens, and at least annually thereafter. If methodology or instrumentation changes, re-evaluate before reporting patient results with the new method. The laboratory director is responsible for ensuring competency is done. For high-complexity testing, the technical supervisor performs and documents testing-personnel competency, and may delegate in writing to a qualified general supervisor. People who do not meet technical consultant, technical supervisor, or general supervisor qualifications cannot be designated to perform those competency assessments.

A one-time hire quiz with no observation, no QC review, and no problem-solving file is not CLIA competency. Chapter 12 taught the documentation shape; this section names the federal procedure list and calendar.

Proficiency testing versus competency

Proficiency testing (PT) asks whether the laboratory can produce acceptable results on unknown samples from a CMS-approved PT program for analytes that require PT. Competency asks whether this person can perform the job. Passing a CAP survey does not replace the six competency procedures. Completing competency does not replace PT or alternative assessment.

CLIA PT rules include testing PT samples like patients (same staff, same methods, same times), not discussing PT with other laboratories before reporting, and investigating unsuccessful events. Many IHC stains are not on the CMS list of required PT analytes the way glucose is. That gap is why accreditors specify PT or alternative performance assessment for predictive IHC. Use a current CMS-approved PT program when PT is required; use the current CAP rules when CAP is the accreditor. Do not invent a universal "all IHC must be in CAP PT" statement, and do not invent the opposite "IHC never needs PT."

When PT or alternative assessment fails, do not hide the score. Investigate, take corrective action, and decide whether patient results from the same period remain reportable—the same operational honesty Chapter 12 required for failed daily controls.

Regulatory questions on this independent guide are U.S.-source questions: CLIA complexity and 493.1253, six competency procedures and the semiannual-then-annual calendar, FDA labeled IVD versus LDT or modified kits, and CAP as a deemed accreditor whose current checklist is the inspection document even when a 2024 guideline is already on your desk.