current version: v1.1.6
released 2013-09-12

Web version

A completely web-based interface for the Quality command-line tool is now in development.

Java version

Current versions of all major browsers no longer support Java applets. If you have an older browser, the Quality Java applet will stay up while we work to match its features with the web version.

Run Java applet

Note: we believe the current Java version as stable and is not being actively updated,
and will not be unless show-stopping bugs are reported. The source is available in JAR format.


The program QUALITY is a variant of the Minimum χ2 (MC) method described by Taswell [2] for limiting dilution assays, and for which he has demonstrated by simulation desirable properties of minimum variance (i.e., high precision) and minimum bias. Our method modifies the MC method to allow the user to specify the probabilities of a false negative and false positive PCR.

The program, and the methods used, are described in detail in Rodrigo et al. [1]. An overview is available in HTML and PDF formats.

  1. Rodrigo, A.G., P.C. Goracke, K. Rowhanian, and J.I. Mullins. 1997. Quantitation of target molecules from PCR-based limiting dilution assays. AIDS Res. Human Retrovir. 13:737-742.
  2. Taswell, C. 1981. Limiting dilution assays for the determination of immunocompetent cell frequencies. J. Immunol. 126:1614-1619.

Native and Source versions

  • Input file format example
  • Current README file, which includes revision history