Clinical laboratory performance on proficiency testing samples--United States, 1994.

Regulation of laboratory testing for human health is mandated by law in the United States; the most recently enacted regulatory law is the Clinical Laboratory Improvement Amendments of 1988 (CLIA). In accordance with this law, as of August 1995 a total of 154,721 laboratories had registered with the Health Care Financing Administration (HCFA), which is responsible for implementing the CLIA regulations. Of these laboratories, only 11% were subject to the federal laboratory practice regulations that existed before the enactment of CLIA. Under CLIA regulations, all laboratories were required to begin participation in a U.S. Department of Health and Human Services (DHHS)-approved proficiency testing (PT) program by January 1, 1994, for a prescribed group of tests (e.g., hematocrit), analytes (e.g., glucose), and testing specialties (e.g., bacteriology) if performed routinely. This report summarizes an assessment of the performance of laboratories participating in PT programs with a certificate of registration from HCFA in 1994 (n = 40,711) and indicates that physician office laboratories (POLs) and other newly regulated testing sites (OTSs) had higher rates of unsatisfactory PT performance than previously regulated hospital and independent laboratories (HIs).