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NIST interlaboratory studies involving DNA mixtures (MIX05 and MIX13): Variation observed and lessons learned

NCJ Number
Forensic Science International: Genetics Volume: 37 Dated: 2018 Pages: 81-94
Date Published
14 pages

This article describes the design of, observations of, and lessons learned from National Institute of Standards and Technology (NIST) interlaboratory studies.


This paper describes National Institute of Standards and Technology (NIST) interlaboratory studies, including the design of these studies, the variations observed among laboratory results, and lessons learned. Interlaboratory studies are a type of collaborative exercise in which many laboratories are presented with the same set of data to interpret, and the results they produce are examined to get a “big picture” view of the effectiveness and accuracy of analytical protocols used across participating laboratories. In 2005 and again in 2013, the Applied Genetics Group of the National Institute of Standards and Technology (NIST) conducted interlaboratory studies involving DNA mixture interpretation. In the 2005 NIST MIX05 study, 69 laboratories interpreted data in the form of electropherograms of two-person DNA mixtures representing four different mock sexual assault cases with different contributor ratios. In the 2013 NIST MIX13 study,108 laboratories interpreted electropherogram data for five different case scenarios involving two, three, or four contributors, with some of the contributors potentially related. (Published Abstract Provided)

Date Published: January 1, 2018