All STATGRAPHICS analyses are validated by comparing the numerical results to one or more sources, including textbooks, journal articles, government benchmarks, hand calculations, and output from other well-established statistical programs. Recognizing that many companies that deal with regulatory agencies such as the FDA are required to validate all software that they use, we will provide registered users with information to help facilitate that process.

Software Quality Control and Validation Methods
Each release of STATGRAPHICS is subjected to rigorous tests before release to the public, both to ensure that it functions properly and to validate the numerical results.  A document describing in detail the procedures employed to test STATGRAPHICS is available upon request. 

The PDF files provided with each statistical procedure outline most of the important calculations performed in that procedure. For many procedures, additional documentation is available with worked examples that can be matched to program output.