Core D: Data Management & Biostatistics Project Summary/Abstract The Data Management and Biostatistics Core (DMBC) will serve as both a collaborator and a valuable resource for all Projects and Cores related to this Program Project. The DMBC will consult on the design of all Projects to assure data collected will adequately address the scientific hypotheses. The DMBC will lead in the application of appropriate statistical and methodological techniques, and collaborate in data analysis and report preparation for all Cores and Projects. The DMBC's role is especially crucial for analysis of associations among longitudinal growth/decline and symptomatic conversion patterns of all disease markers across all Projects and Cores. The significance of the Data Management and Biostatistics Core is to provide a central and relational program-wide high quality database and assure analytic integrity of all publications from the ACS. It is the mission of the DMBC to enhance and support the research objectives of the ACS by providing timely and reliable data management and appropriate analytic expertise across the Program Project.