team a demonstration of REDCap, highlighting the most relevant user interface features. The researchers then fill out a Microsoft Excel spreadsheet file with key metadata (i.e. field name, data-type, data range, etc.) about each measurement in their CRF. The informatics core converts this spreadsheet template into study-specific database tables which are linked to a working web-based EDC forms and applications environment. The researchers then test this prototype web application by filling out dummy data, and the metadata spreadsheet is revised and refined in an iterative process. Once the REDCap project design is finalized, the application is deployed from development to production mode, all dummy data is lost, and researchers begin committing actual patient data. The REDCap design workflow has important limitations. When a project is deployed into production mode, further revisions in database design need to be approved by the informatics core. Furthermore, certain production mode revisions are simply not allowed. For instance, when applying the REDCap calendar tool, production mode revisions to calendar metadata is prohibited, so researchers are advised to be very careful in formulating metadata and event-handlers before committing to the inflexibility of production mode. References Freeware Medical databases