CLIA test complexity explained
What waived, moderate and high complexity mean, how a test gets its category, and what it means for the people who run it. Cited to the CFR, FDA and CMS.
The three categories
Under 42 CFR 493.5, every lab test is one of: waived, moderate complexity (including provider-performed microscopy, PPM) or high complexity. A lab must be CLIA-exempt or hold a certificate that matches what it runs: registration, waiver, PPM, compliance or accreditation.
Waived tests
Waived tests are simple procedures that are cleared by FDA for home use, use methods so simple and accurate that wrong results are unlikely, or pose no reasonable risk of harm if done wrong (42 CFR 493.15(b)). The rule lists examples such as non-automated dipstick urinalysis, urine pregnancy tests by visual color comparison, and blood glucose by FDA-cleared home-use monitors.
Moderate vs high: the scorecard
For everything else, FDA scores the test on seven criteria, 1 to 3 points each (42 CFR 493.17):
- Knowledge
- Training and experience
- Reagents and materials preparation
- Characteristics of operational steps
- Calibration, quality control and proficiency testing materials
- Test system troubleshooting and equipment maintenance
- Interpretation and judgment
A total of 12 or less is moderate complexity; above 12 is high complexity. FDA categorizes a test after clearing or approving it, or on request for legally marketed devices (FDA: CLIA Categorizations).
Look up a test
Opens FDA's official database in a new page. Search by test system, analyte or manufacturer.
Who may perform the testing
Moderate complexity testing personnel must meet 42 CFR 493.1423 and high complexity testing personnel must meet 42 CFR 493.1489, plus hold a state license where the state requires one. See which apply to you with the Path Finder.
Common questions
What are the three CLIA test categories?
Waived tests, tests of moderate complexity (including provider-performed microscopy, PPM) and tests of high complexity, under 42 CFR 493.5.
Who decides a test's complexity?
FDA. Tests waived by regulation or cleared for home use are waived; otherwise FDA scores the package insert instructions on seven criteria. A total of 12 or less is moderate complexity and above 12 is high complexity (42 CFR 493.17).
How do I look up a specific test?
Search FDA's CLIA database by test system, analyte or manufacturer to see its complexity.
Sources
- 42 CFR 493.5, 493.15, 493.17, 493.1423, 493.1489 (eCFR, current to Oct 15, 2026)
- FDA: CLIA Categorizations and FDA CLIA database
- CMS: Clinical Laboratory Improvement Amendments (CLIA)
Checked against these sources on Oct 18, 2026. Reference only, not legal advice.