Modified Project Summary/Abstract Section PROGRAM SUMMARY/ABSTRACT CORE G: BIOSTATISTICS Data used for HIV research are constantly increasing in complexity, volume and availability. This enables researchers to investigate myriad questions related to HIV, from the molecular to the population and policy levels, and often at multiple levels at once. Biostatistical methods and their principled application are therefore fundamental to rigorous, reproducible HIV research. Core G will provide CFAR investigators with the collaborative expertise required for study design, data analysis, and contextual interpretation of data that are required for rigorous, reproducible research that advances scientific knowledge about HIV. The purview and expertise of Core G faculty and staff includes framing of research questions, study design, sampling, computation, data analysis (including development of new methods as needed), data management, and interpretation of analysis results in context. Core G will collaborate with and support HIV researchers and trainees by meeting the following Specific Aims: (1) providing wide-ranging biostatistical collaboration to CFAR scientists, with emphasis on early stage investigators; (2) developing, implementing and disseminating new statistical method to meet the research aims of CFAR scientists; (3) providing ongoing training and mentoring through workshops and 1:1 mentoring; (4) promoting cross-CFAR, cross-program and other collaborations with HIV researchers; and (5) providing guidance and support for analyzing and accessing electronic health records data from Brown- and BU-affiliated hospitals.