When it comes to statistical analysis, without doubt, SAS is the best choice and the tool of choice. I really can't think of any tools which can offer the same level of flexibility for analyzing the data. Below is an excerpt from a book which echos the same opinion:
While consulting for dozens of companies over 25 years of statistical application to clinical investigation, I have never seen a successful clinical program that did not use SAS.
--Preface,Common Statistical Methods for Clinical Research with SAS Examples, Glenn A. Walker
