Validation Resources


Participants: John M. Butler


Project Timeframe: June 2004 to present


Purpose: Validation involves performing laboratory tests to verify that a particular instrument, software program, or measurement technique is working properly. These validation experiments typically examine precision, accuracy, and sensitivity, which all play a factor on the 3 R’s of measurements: reliability, reproducibility, and robustness.


Progress: Efforts have been made to catalog and summarize validation studies that have been published in the literature. The purpose of this effort is to provide details on studies conducted, a description of samples tested, and the number of samples run as part of the study in order to aid current and future validation efforts by forensic DNA laboratories. Validation training information has also been presented to the community in the form of publications, presentations, and workshops. More information on this effort can be found in the STRBase validation section:


Publications or Presentations Resulting From This Project:

Butler, J.M. (2007) Validation: what is it, why does it matter, and how should it be done? Forensic News (Applied Biosystems), January 2007 [.pdf]


Butler, J.M. (2006) Debunking some urban legends surrounding validation within the forensic DNA community. Profiles in DNA (Promega Corporation), vol. 9(2), pp. 3-6; see also


Butler, J.M., Tomsey, C.S., Kline, M.C. (2004) Can the validation process in forensic DNA typing be standardized? Proceedings of the 15th International Symposium on Human Identification. Available at  or

John Butler workshop for Pennsylvania State Police DNA Lab (Greensburg, PA), June 5, 2007 "Validation Workshop and Other Topics" [Validation] [qPCR and LCN Issues]

John Butler presentation for Validation Workshop at Applied Biosystem's HID University/Future Trends in Forensic DNA Technology seminar series (Albany, NY), May 10, 2006, "Validation Workshop" [.pdf]

John Butler and Robyn Ragsdale validation workshop at the National Forensic Science Technology Center (Largo, FL), August 24-26, 2005 [Introductions] [Validation Overview] [Introduction to DAB Standards] [Developmental Validation] [Inconsistencies in Validation Between Labs] [Internal Validation] [Method Modifications and Performance Checks]


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Last updated: 06/20/2007


Disclaimer: This project was supported by National Institute of Justice Grant Number 2003-IJ-R-029, which is an interagency agreement between NIJ and the NIST Office of Law Enforcement Standards, awarded by the National Institute of Justice, Office of Justice Programs, US Department of Justice. Points of view in this document are those of the authors and do not necessarily represent the official position or policies of the US Department of Justice. Certain commercial equipment, instruments and materials are identified in order to specify experimental procedures as completely as possible.  In no case does such identification imply a recommendation or endorsement by the National Institute of Standards and Technology nor does it imply that any of the materials, instruments or equipment identified are necessarily the best available for the purpose.