The acronym CLIA stands for Clinical Laboratory Improvement Amendments. In 1988, Congress passed CLIA to establish quality standards that would apply to laboratory testing nationwide. The standards ensure that, regardless of location, all clinical testing on human specimens is performed with accuracy, reliability, and timeliness. In 1992, CLIA’s final regulations distinguished between levels of test complexity. Three categories were established: waived complexity, moderate complexity (includes the subcategory of provider-performed microscopy [PPM]), and high-complexity testing. Permission to perform clinical laboratory testing in any or all categories requires the laboratory director to submit an application to enroll in the CLIA program, pay the applicable fee, and meet quality requirements that correspond to the type of certificate that is obtained. The 10–1–04 edition of 42 CFR Ch. IV, Part 493, the most current version of CLIA regulations, is the source used to write this introduction (available at wwwn.cdc.gov/clia/pdf/42cfr493_2004.pdf).

A Certificate of Waiver (COW) obtained by the appropriate health-care provider (HCP) allows qualified nursing or other health-care personnel to perform procedures classified as waived testing in an HCP’s office or in a hospital nursing unit. Waived testing includes tests that are cleared by the U.S. Food and Drug Administration (FDA) for home use, have manufacturers’ instructions to follow, and pose no harm to the patient if testing is performed incorrectly. The testing process utilizes controls. Examples of waived testing include dipstick urinalysis, fecal occult blood, ovulation testing, urine pregnancy tests, erythrocyte sedimentation rate (nonautomated), hemoglobin (copper sulfate method), blood glucose (on glucose meters cleared by the FDA), spun hematocrit, and hemoglobin by single analyte instruments that are self-contained with direct measurement and readout. Over 100 analytes, used in a variety of test systems and that can be performed on eight different specimen types, have been waived. Specific information can be obtained at www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfClia/analyteswaived.cfm.

In addition to waived testing, PPM testing can be performed in an HCP’s office. A PPM certificate obtained by a physician or midlevel practitioner allows the practitioner to perform PPM testing on specimens obtained during the patient’s office visit. A midlevel practitioner can perform this type of testing under the direct supervision of a physician or in independent practice if authorized by the state. A microscope is utilized to view the specimens during the patient’s office visit. PPM tests are performed on specimens in situations in which the accuracy of the findings would be compromised if a delay in testing were to occur. The testing process has no available controls. Examples of PPM testing include urine sediment examinations; potassium hydroxide preparations; pinworm examinations; fern tests; nasal smears for granulocytes; fecal leukocyte examinations; qualitative semen analysis (limited to determining the presence or absence of sperm and detection of motility); postcoital direct; qualitative examinations of vaginal or cervical mucus; and wet-mount testing for the presence or absence of bacteria, fungi, parasites, and cellular elements.

Hospital and reference laboratories perform tests of moderate and high complexity. The laboratory director must obtain the corresponding CLIA certificate and have personnel qualified to perform tests of moderate and high complexity.