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 PredictiveProbabilit_V1.5.0_WithFX4.0.zip  58696 KB Includes Microsoft .Net Framework 4.0
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Predictive Probabilities

This software provides predictive probability analysis of two-arm clinical trials. The software computes the posterior predictive probabilities concluding that one arm or the other is superior or stopping a trial due to futility. This software is often used in designing clinical trials and in conducting interim analyses.

The software supports clinical trials in which the primary endpoint is binary or time-to-event (TTE).

Note that although the user interface focuses on two-arm trials, one can use the software to analyze single-arm trials by specifying the number of observations on one of the arms to be zero.

See the Predictive Probabilities User's Guide for more information.

What's New in Version 1.5

  • Minor bug fixes and other improvements
  • Occasionally sends usage statistics and crash reports to our biostatistics software support team to improve your experience using the software


  • Windows 7
    (other Windows versions may be compatible but this has not been tested)
  • Administrative permissions may be required to install Predictive Probabilities depending on the chosen installation location.
  • The following packages will be installed if they are not present:
    • Microsoft .Net 4.0 Framework
    • Microsoft Visual C++ 2010 x86 Redistributable 10.0.40219
    • Microsoft Windows Installer 3.1
  • To view the Predictive Probabilities User's Guide a PDF file viewer (not included with the software) such as Adobe Reader (available for free here) must be installed.
  • To follow the "Send feed back via email" link in the Help -> About window, an email client such as Microsoft Outlook (not included with the software) must be installed.

Predictive Probabilities screenshot

See Predictive Probability Interim Analysis for a brief explanation of the statistics behind this software. See also the online documentation.

See also on this site Phase II Predictive, software using Bayesian predictive probability in the design of phase II clinical trials.

J. Kyle Wathen developed the first version of the software, using C# for the user interface and C++ for the numerical calculations. Hoang Nguyen and Clift Norris developed version 1.3. John Cook and Clift Norris developed version 1.4. John Venier developed version 1.5.