The purpose of the Biostatistics, Modeling, and Data Management Core (Core C) is to provide a comprehensive, multi-disciplinary resource for the design of all experiments, development of appropriate and innovative statistical methodology, development and application of appropriate kinetic models to intrepret the data, statistical analysis, and summarization of results. The Core has the following overall goals: to provide statistical and modeling consulting and collaboration on the design, conduct, analysis and interpretation of all project research studies and cores, and to provide, manage and maintain a high-quality research database that supports the research projects and cores while preserving the confidentiality of all subject data. The specific aims are to: (1) Coordinate and manage statistical activities to ensure investigators have ready access to statistical consultation and support. (2) Provide statistical expertise in the design of experiments and studies, including research proposal development, analysis methods, sample size determination, randomization procedures, and plans for interim reviews and final analysis. (3) Provide kinetic modeling expertice for all projects using imaging to measure physiologic parameters. (4) Provide data analysis and extraction to obtain the necessary information from project data. (5) Assist with the writing of statistical and modeling components of manuscripts. (6) Review the integrity and statistical soundness of all studies. (7) Maintain a computing facility with up-to-date software for statistical analysis to support all project investigators. (8) Conduct biostatistical methodology research on practical problems arising from performance of the projects. (9) Develop new modeling approaches as necessary to maximize the utility of each investigator's data. (10) Provide computer-based tools that facilitate the storage and retrieval of the data generated in the proposed research, thereby creating and maintaining a centralized relational database that provides access to common resources and information. (11) Ensure the accuracy of the data maintained in the database by software based data consistency and quality control systems. (12) Organize and maintain the database to maximize accuracy and accessibility while maintaining strict confidentiality. (13) Provide detailed descriptions of the available populations and resources for current and future investigators. (14) Provide high-quality data entry services.