In the past, NIST coordinated several quality assurance programs that participants used to identify and understand community-wide measurement challenges, improve the accuracy of their measurements, and demonstrate an effort to comply with various regulations. These programs offered the opportunity for laboratories to assess their in-house measurements, and participation in a quality assurance program in conjunction with the use of SRMs has been shown to improve the comparability and precision of data over time, as shown below.
The NIST Clinical Quality Assurance Program (ClinQAP) served two key functions in the clinical measurement community. The first was to support the long-term reliability of micronutrient, vitamin D metabolite, and fatty acid measurements in serum and plasma matrices through the Micronutrients Measurement Quality Assurance Program (MMQAP), the Vitamin D Metabolites Quality Assurance Program (VitDQAP), and the Fatty Acids in Human Serum and Plasma Quality Assurance Program (FAQAP), respectively. Results from the comparison studies helped participants to make accurate clinical and health-care decisions as well as to maintain and improve their measurement comparability. The second function of the ClinQAP was to monitor and support the emerging measurement needs of the clinical community and to expand the range of analytes and matrices studied. The ClinQAP concluded in 2017, and parts of the ClinQAP community will now be served through the HAMQAP.
NIST established a Dietary Supplement Laboratory Quality Assurance Program (DSQAP) in 2007 in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements (ODS). Participants measured concentrations of active and/or marker compounds and nutritional and toxic elements in samples distributed by NIST. Data were compiled at NIST where they were analyzed for accuracy, precision, and concordance within the community. Reports and certificates of completion were sent to participants, and workshops were held to discuss results as well as methodological advancements in the characterization of dietary supplements. The DSQAP concluded in 2018, and parts of the DSQAP community will now be served through the HAMQAP.
The marine mammal interlaboratory comparison program was initiated in the early 1990s as informal comparisons among NIST, NOAA, and several other laboratories. By 2000, the measurement of trace elements and organic contaminants in marine mammal tissues was formalized in annual or biennial interlaboratory exercises. Since that time, participation has increased dramatically both domestically and internationally. In addition to providing an assessment of interlaboratory measurement comparability, the organic contaminant exercises have also provided information on new constituents, including fatty acids and brominated flame retardants in SRM 1945 Organics in Whale Blubber, which has been used routinely as a control material for the exercises. The trace element exercise has resulted in the development of three trace element control materials from marine mammal livers, a pilot whale liver homogenate in 1991 and beluga whale and pygmy sperm whale liver homogenates in 1997 and 2003, respectively.
Until 2000, these intercomparison exercises were carried out with financial support from both NOAA and NIST. Beginning in 1993, laboratories not directly involved with NOAA programs (e.g., private laboratories) were allowed to participate in the exercises by paying a participation fee. Since 2000, NIST has required all laboratories participating in the organic exercises to pay the participation fee, which partially covers the costs of the program. In 2010, NIST supported the NOS Office of Response and Restoration in underpinning collection and measurement of samples relating to the Deepwater Horizon Oil spill. This was done by providing (1) protocols for the collection and storage of marine samples and (2) conducting a series of four interlaboratory comparison exercises to help assess data quality among laboratories providing data to be used in the damage assessment.