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RAT-STATS - Statistical Software

RAT-STATS is a free statistical software package that providers can download to assist in a claims review. The package, created by OIG in the late 1970s, is also the primary statistical tool for OIG's Office of Audit Services.

Among other tasks, the software assists the user in selecting random samples and estimating improper payments. We have attempted to make RAT-STATS as user-friendly as possible, keeping in mind the program uses technical statistical terms. OIG does not provide technical support for RAT-STATS.

Although OIG does not require the use of RAT-STATS, many providers download the software in their efforts to fulfill the claims review requirements for corporate integrity agreements or provider self-disclosure protocol.

Download RAT-STATS 2010 for Windows (ZIP)

  • Extract zip files to a folder on your hard drive.
  • Run setupRATSTATS2010v4.exe and follow the installation instructions.

Download RAT-STATS 2019 for Windows (ZIP)

  • Extract zip files to a folder on your hard drive.
  • Run RATSTATS.exe. You may find it helpful to create a shortcut to the executable for future use.
  • We are currently working on creating a user guide for the updated software.

The user explicitly acknowledges that all shareware obtained from this site is provided 'as is' without warranty of any kind, expressed or implied, including, but not limited to the warranties of merchantability and fitness for a particular purpose and that the risk of using shareware obtained from this site, including the entire costs of all necessary remedies, is with that user.


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