CORE 1 ABSTRACT The Administration, Biostatistics and Clinical Database Core provides support for all three projects within the P01. The PI, Dr. Ferrara, is responsible for the overall conduct of this research program. An executive committee of members (the three project and core leaders) is chaired by the PI. The executive committee meets formally on a monthly basis to review progress of the individual projects, to monitor the function of the cores, and to resolve any potential logistical difficulties. Umut Özbek, Ph.D., provides biostatistical oversight to all projects with expertise in three categories of statistical services: 1) statistical analysis of clinical and biomarker data; 2) experimental design, sample size calculations and analyses in experimental models; and 3) clinical trial design and monitoring. Dr. Levine oversees the activities of the data coordinating center which provides a number of innovative and cost effective services. The MAGIC database currently contains data for 5,000 HCT recipients and 2300 acute GVHD cases; ~700 patients (300 with GVHD) per year. This core has developed rigorous processes to minimize data errors both before and after data entry. The Core 1 objectives are as follows: 1. To provide administrative and fiscal oversight to all projects and cores, and to facilitate optimal interactions including centralized data sharing, document generation, organization monitoring, financial reports, and accountability to all internal and external agencies. 2. To provide advanced biostatistical support for analysis of clinical and laboratory data and assist in the biostatistical design of experiments in all projects. 3. To oversee the creation and curation of the MAGIC database.