Reproducibility and specificity concerns associated with nucleic acid amplification tests for detecting Chlamydia trachomatis



Commercial nucleic acid amplification tests (NAATs) have become one of the most frequently used tests for detecting Chalmydia trachomatis. However, published studies have raised important concerns regarding the NAAT evaluation process in general and their reproducibility and clinical specificity in particular. This is because for many infectious diseases including chlamydia, a true gold standard simply does not exist and, as a result, estimation of test performance parameters in the absence of a gold standard is a difficult and challenging task. In this manuscript, we will attempt to address some issues pertaining to the evaluation of NAATs including NAAT reproducibility, test validity, and the manner in which positive NAAT results are confirmed. Finally, we will discuss some of the potential clinical and public health implications of testing by NAATs.



A version of this paper was posted in a non-peer reviewed website hosted by the University of Washington in June 2007. Go to and search for Hadgu.


The views expressed in this article are those of the authors and do not necessarily reflect the views or policies of the Centers for Disease Control or the U.S. Public Health Service.


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© US Government 2008

Authors and Affiliations

  1. 1.Division of STD PreventionCenters for Disease Control and PreventionAtlantaUSA

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