The Biostatistics and Data Management (BDM) Core consitutes the central resource for all statistical and data management needs of the program project. Data generated by each of the research projects will be transferred to the Database Component for entry and storage in an integrated SIR2002 data management system designed to meet all the needs of the projects with respect to cleaning, organization and retrieval of data for planned and ad hoc analyses. These activities will be carried out by a data manager and a data entry clerk working under the supervision of the Core director on a fire-wall protected networked system of work stations and mirrored file servers. The Statistics Component will be responsible for coordinating the implementation of all planned analyses conducted by investigators in the clinical trials, functional imaging study and the educational and behavior intervention. The core will advise continually on and thereby enhance, the performance of the two clinical trials according to the highest standard of conduct for randomized controlled trials: appropriate methods to ensure randomization, blinding and subject compliance will be maintained. State-of-the-art techniques for the statistical analysis of imaging data will be applied. Each statistician will work closely with the P.I. of one project, with overall statistical and data-related review of all projects provided through regularly scheduled meetings of the BDM Core with the Principal Investigator and project investigators. The BDM Core will also work closely with Core A with respect to patient recruitment, and with Core D with respect to integration of results obtained from analysis of blood and tissue specimens.