CLIA or Clinical Laboratory Improvement Amendments was established to develop quality control standards for the entire laboratory testing industry to make certain the veracity, consistency and relevancy of the test results regardless of where the test was being performed. The classification of “in vitro diagnostic tests” under CLIA regulations is the responsibility of the FDA.

FDA could transfer commercially distributed in-vitro diagnostic testing products to one of three CLIA regulatory classes according to their probable risk to public health:

Physician office testing laboratories, which were in charge for less then 10% of the total quantity of reportable test results in the United States, usually carry out less complex tests than hospital or sovereign testing laboratories. The list of tests that are suitable for the small medical office include:
 LH Ovulation urine tests
 Fecal occult blood test kit
 Urine pregnancy tests
 Thyroid Stimulating Hormone (TSH) 
 Strep A test
 Assortment of Drug Test Kits
 Glucose and A1C blood test
And almost any other tests listed in CLIA waived.

Reimbursement for these types of tests is approximately 30% to 45% lower than for the typical text mix at hospitals or independent labs.

The highest volume waived tests are:
Prothrombin (25.4 million tests/year)
Urinalysis (23.5 million tests/year)
Oovulation (13 million tests/year)
Glucose (12 million tests/year)
FOBT (11.5 million tests/year)
The lipid panel (5.5 million tests/year).
CLIA-waived tests represent about $1 billion in annual laboratory testing revenue and, according to specialists’ prognose, are expected to grow more than 20% a year.