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Micronutrients Measurement Quality Assurance Program


Since 1984, the National Institute of Standards and Technology (NIST) has coordinated the Micronutrients Measurement Quality Assurance (QA) Program for laboratories that measure vitamins and carotenoids in human serum and plasma. Interlaboratory comparison studies are currently directed toward the measurement of retinol, gamma-tocopherol, alpha-tocopherol, beta-carotene, and ascorbic acid. Laboratories also report values for delta-tocopherol, retinyl palmitate, alpha-carotene, lycopene, beta-cryptoxanthin, lutein, zeaxanthin, 25-hydroxyvitamin D, coenzyme Q10, vitamin K1, and other related measurands. Frozen or freeze-dried sera are sent to laboratories biannually (winter and spring) for analysis. Results are then returned to NIST for data evaluation and tabulation. Value-assignment of the sample pools is based on the median of all the laboratory results, with confirmation based on measurement at NIST using two or more different methods. Consultation and troubleshooting regarding methods of analysis are also provided. A micronutrient analysis QA workshop for fat-soluble vitamin and carotenoid analysis and for ascorbic acid in serum analysis is hosted as well. A certificate of participation in the QA program, which displays the laboratory's measurement performance summary for all analytes reported, is issued at the end of each calendar year.

Study Reports

Reports for intercomparisons from 1996 onward are available:

NIST Interagency/Internal Report (NISTIR) 7880-28

NIST Interagency/Internal Report (NISTIR) 7880-27

NIST Interagency/Internal Report (NISTIR) 7880-26

NIST Interagency/Internal Report (NISTIR) 7880-25

NIST Interagency/Internal Report (NISTIR) 7880-24

NIST Interagency/Internal Report (NISTIR) 7880-23
NIST Interagency/Internal Report (NISTIR) 7880-22 

NIST Interagency/Internal Report (NISTIR) 7880-21 
NIST Interagency/Internal Report (NISTIR) 7880-20

NIST Interagency/Internal Report (NISTIR) 7880-19
NIST Interagency/Internal Report (NISTIR) 7880-18

NIST Interagency/Internal Report (NISTIR) 7880-17
NIST Interagency/Internal Report (NISTIR) 7880-16

NIST Interagency/Internal Report (NISTIR) 7880-15
NIST Interagency/Internal Report (NISTIR) 7880-14

NIST Interagency/Internal Report (NISTIR) 7880-13
NIST Interagency/Internal Report (NISTIR) 7880-12

NIST Interagency/Internal Report (NISTIR) 7880-11
NIST Interagency/Internal Report (NISTIR) 7880-10

NIST Interagency/Internal Report (NISTIR) 7880-9
NIST Interagency/Internal Report (NISTIR) 7880-8

NIST Interagency/Internal Report (NISTIR) 7880-7
NIST Interagency/Internal Report (NISTIR) 7880-6

NIST Interagency/Internal Report (NISTIR) 7880-5
NIST Interagency/Internal Report (NISTIR) 7880-4

NIST Interagency/Internal Report (NISTIR) 7880-3 
NIST Interagency/Internal Report (NISTIR) 7880-2

NIST Interagency/Internal Report (NISTIR) 7880
NIST Interagency/Internal Report (NISTIR) 7880-1

Program Costs (for 2014)


Exercises Per Year

Annual Participation Fee

Annual Participation Fee

Fat-Soluble Vitamins and Carotenoids in Serum




Vitamin C in Serum




How to Join the Program

If you are interested in joining our program, please download and print the enrollment form (PDF format). You may also obtain more information or enroll by contacting the Micronutrients Measurement Quality Assurance Program at the address shown below.

Micronutrients Measurement Quality Assurance Program
100 Bureau Dr, Stop 8392
Gaithersburg, MD 20899-8392
Fax:  301-977-0685

Related Standard Reference Materials (SRMs) 968e and 970

srm 968eWe recommend that labs obtain Standard Reference Material (SRM) SRM 968e Fat-Soluble Vitamins, Carotenoids, and Cholesterol in Human Serum and SRM 970 Ascorbic Acid in Human Serum at the outset of their participation in the QA program to validate their methodology and to value assign in-house control materials. These SRMs may be purchased from the Office of Reference Materials at NIST (301-975-2200; fax: 301-948-3730; or e-mail:

Micronutrients Measurement Quality Assurance Workshop

This workshop is intended for laboratories that measure vitamins and carotenoids in human serum and plasma as part of the QA program. This workshop provides a forum for participants to discuss analytical methods, results of the intercomparison exercises, and other related topics. There is no registration fee.

Related Publications

  1. Brown Thomas. J.; Kline, M.C.; Gill, L.M.; Yen, J.H.; Duewer, D.L.; Sniegoski, L.T.; and Sharpless, K.E. Preparation and Value Assignment of Standard Reference Material 968c Fat-Soluble Vitamins, Carotenoids, and Cholesterol in Human Serum, Clin. Chim. Acta., 305 (2001), 141-155.
  2. Duewer, D.L., Brown Thomas, J., Kline, M.C., MacCrehan, W.A., Schaffer, R., Sharpless, K.E., May, W.E., NIST/NCI Micronutrients Measurement Quality Assurance Program: Measurement Reproducibility, Repeatability, Stability, and Relative Accuracy for Fat-Soluble Vitamin-Related Compunds in Human Sera, Anal. Chem. 69 (1997), 1406-1416.
  3. Duewer, D. L.; Kline, M. C.; Sharpless, K. E.; Brown Thomas, J. M.; Gary, K. T.; Sowell, A. L. Micronutrients Measurement Quality Assurance Program: Helping Participants Use Interlaboratory Comparison Exercise Results to Improve their Long-term Measurement Performance. Anal. Chem. 71 (1999) 1870-1878.
  4. Duewer, D. L.; Kline, M. C.; Sharpless, K. S.; Brown Thomas, J. NIST Micronutrients Measurement Quality Assurance Program: Characterizing Individual Participant Measurement Performance Over Time, Anal. Chem., 72(15) (2000), 3611-3619.
  5. Duewer, D. L.; Kline, M. C.; Sharpless, K. S.; Brown Thomas, J. NIST Micronutrients Measurement Quality Assurance Program: Characterizing the Measurement Community's Performance Over Time. Anal. Chem. 72(17) (2000), 4163-4170
  6. Margolis, S. A.; Duewer, D. L. The Measurement of Ascorbic Acid in Human Plasma and Serum: Intralaboratory Repeatability, Interlaboratory Repeatability, Interlaboratory Reproducibility, and Stability in Lyophilized Plasma and Metaphosphoric Acid Preserved Plasma and Serum. Clin. Chem. 42 (1996), 1257-1262.
  7. Margolis, S.A., Vangel, M., and Duewer, D.L., Certification of SRM 970, Ascorbic Acid in Serum, and the Analysis of Associated Interlaboratory Bias in the Measurement Process, Clin. Chem., 49 (2003), 463-469.
  8. Sharpless, K. E.; Duewer, D. L. Population Distributions and Intralaboratory Variance for Fat-Soluble Vitamin-Related Compounds in Human Serum. Anal. Chem. 67 (1995), 4416-4422.

Jeanice Brown Thomas
301-975-3120 Phone

David L. Duewer
301-975-3935 Phone

301-977-0685 Facsimile

100 Bureau Drive, M/S 8392
Gaithersburg, MD 20899-8392