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Benchmark Dose Tools

Download CatReg

Download CatReg (rel. 2017-06-16)

For Microsoft Windows 7 or later 

The CatReg download package includes the most current version of the CatReg software for Windows. The download package also includes sample data files and the CatReg User Guide in PDF.  

On this page:

Downloading and Installing the Software

CatReg can be installed to any folder where the user has create/read/write privileges. Administrator privileges are not required.

You do not need to uninstall previous versions of CatReg. You can run this version of CatReg alongside earlier versions.
  1. Right-click and select “Save Target As” or “Save Link As” for the  CatReg 3.1 Windows Installer file (.msi)(1 pg, 4 MB) . It is highly recommended that all CatReg users download and install this new version.
  2. Run the CatReg31.msi file. Your system’s antivirus program may warn you about the file; if so, approve or allow the file so the install can continue.
  3. Step through the install wizard. You can enter a different install directory or accept the default.
  4. Navigate to the install directory and select the CatReg.exe file to start the program.
When installing the CatReg application folder, you should:
  • Place the CatReg application folder (and its subfolders) in the simplest, shortest directory possible. For most EPA users, the preferred path would be C:\Users\[EPA user's LAN ID]; for non-EPA users, this could be as simple as C:\.
  • Ensure there are no special characters or spaces in the folder names.
Refer to the ReadMe.pdf in the CatReg application folder for details on known issues or other information that did not make it into the user guide.

If you have problems or concerns, please contact us using our Help Desk Form.

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System Requirements

  • 16 Megabytes of RAM
  • Microsoft Windows 7 or later.
  • Microsoft .NET 4.5 or later. If your computer is set up to allow or be notified of downloads of Microsoft software, then it is likely that that version of the .NET framework is already installed. Otherwise, you can download and install Microsoft's latest version of .NET for client desktops. Exit
  • R for Windows Exitversion 3.4 or later (either 32- or 64-bit). CatReg relies on the open source package R for Windows to perform all statistical calculations.

Note: There are no plans at this time to create Macintosh or Linux versions of CatReg.

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Uninstalling Older CatReg Versions (Optional)

You do not need to uninstall previous versions of CatReg. 

However, if you want to uninstall previous versions of CatReg, it is recommended that you retain the directory structure for the folders holding your previous model runs' input and output data files. Keeping those files and folders in place will maintain the functionality of your previous CatReg sessions.

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R-only CatReg Version

You can also download CatReg 2.3, the R-only version of the software released in 2012, along with sample data files and a PDF user guide. You must download and install the latest version of the R statistical softwareExit to run this CatReg version.

None of the statistics in 2.3 have changed in CatReg for Windows, except that the Windows version provides automatic hypothesis testing.

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Receive Updates on New Releases

Registration is not required to download the software. However, you can sign up to receive an email to learn about new releases or important information.

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