Reference material needs in clinical laboratory science

In 1968, clinical chemistry was considered to be the field most in need of certified reference materials (CRMs). While significant progress has been made in this area, new diagnostic assays are continually being developed that create a need for new CRMs. Members of the clinical laboratory community help to identify reference material needs. Professional and governmental organizations, such as IFCC, AACC, NCCLS, CDC, and the national metrological institutes (NMIs), respond to develop protocols and materials. Several measurands are presented as examples. In the late 1950s and early 1960s, in response to a need for standardization of lipid and lipoprotein measurements, CDC developed a reference system that included secondary reference materials. Over the years, the process of preparation of these materials was refined, eventually leading to the development of NCCLS guideline for preparation of commutable frozen serum pools for use as secondary reference materials (C37-A). This protocol was used for the preparation of NIST SRM 1951a (lipids in frozen (liquid) human serum). In the 1980s, a need for a reference material for blood lead was identified. CDC and NIST cooperated to develop SRM 955 (lead in bovine blood). More recently, efforts have been initiated to standardize high-sensitivity C-reactive protein (hsCRP) assays. In this case, a CRM for CRP existed (CRM 470, developed by IFCC and available from IRMM), but at concentrations in the acute phase reactant range and not in the low range needed for hsCRP assays. CDC coordinated a study to evaluate diluted CRM470 and other candidate materials as secondary reference materials for hsCRP assays.