Status: Version 2 - 1st June 2016 Working Group Goals: The NIH BD2K bioCADDIE Metadata Working Group (WG) 3 is tasked to define a set of metadata specifications that support intended capability of the NIH BD2K Data Discovery Index prototype, DataMed - as outlined in the bioCADDIE White Paper. Abstract. The DATS model has been designed to support the intended capability of the NIH BD2K Data Discovery Index prototype, outlined in the bioCADDIE White Paper and named DataMed. The DATS model and its serialization describe the metadata and the structure for datasets needed to populate the DataMed prototype, along the line of the Journal Article Tag Suit (JATS) used by PubMed for literature. The DATS has been designed to have core and extended elements, to progressively accommodate more specialized data types, as needed. Intended Audience. This document is aimed at: (i) the DataMed development team that will implement and test the model, (ii) prospective data sources that wish to be indexed in the DataMed prototype, including those attending the DataMed repository workshop in June 2016, and (iii) developers of data harvesting and other metadata tools and catalogs. Contact: Questions and comments to Susanna-Assunta Sansone (WG3 chair) and WG3 members - adding them directly to the live Google document or sending them to biocaddie[at]ucsd.edu.