Every clinical blood test in the United States runs inside a federal regulatory framework, and understanding that framework answers a fair question: who checks that a laboratory's results can be trusted?
CLIA certification is the legal floor.
The Clinical Laboratory Improvement Amendments (42 CFR Part 493) govern every laboratory that tests human specimens for health assessment in the United States. CLIA-certified laboratories must validate the accuracy, precision, and reportable range of their tests, employ qualified personnel, run documented quality control, and pass regular inspections. The same rules apply to a hospital lab, a national reference lab, and a specialty lab.
CAP accreditation is a higher bar.
The College of American Pathologists runs an accreditation program, recognized by federal regulators, in which laboratories are inspected by practicing laboratory professionals against checklists that exceed CLIA's minimums. Many leading academic and reference laboratories choose CAP accreditation precisely because it is more demanding.
Laboratory-developed tests are a normal part of American medicine.
Not every clinically useful test has a commercial FDA-cleared kit. Laboratory-developed tests, validated and performed within a single certified laboratory, are how much of specialized diagnostics is delivered, and the FDA has estimated tens of thousands are in clinical use. What matters is the certification and validation framework the laboratory operates under.
The biomarker testing described in this section is performed in laboratories operating under CLIA certification, and the markers themselves, GFAP, UCH-L1, S100B, and neurofilament light, are the same proteins measured in the FDA-cleared acute tests and in the published research cited throughout this site [, , , , , , , ].