Theradex biostatisticians have a wealth of expertise in designing studies with the appropriate sample size and endpoints. At the protocol design stage, various scenarios can be accommodated in estimating sample sizes appropriate for a variety of assumptions. Assumptions include variations of endpoint differences based upon response rates, survival rates and improvements in overall patient well-being. Theradex biostatistical staff have broad experience in the planning of analyses for multinational studies incorporating many hundreds and thousands of patients. Theradex biostatisticians are also accustomed to ongoing dialogues with regulatory authorities to ensure concurrence in the appropriateness of analyses. These dialogues continue up through preparations for market approval. Additionally, the biostatistical staff assist the computer and regulatory groups in the preparation of CANDAs, and incorporate the necessary data tabulations for further regulatory analysis and graphical displays into sophisticated imaging media.