HIV cohort collaborations have made substantial contributions to the knowledge of HIV epidemiology and management over the last years. So far, most collaborations have incorporated slightly different protocols for data exchange causing unnecessary workload for the people in charge of data extraction.

We were therefore asked to put together this draft consensus protocol for discussion at the 7th International Workshop on HIV Observational Databases, March 29th-30th 2003, Fiuggi, Italy. It is based on our experience with data-exchange protocols for ​D:A:D, the ​ART Cohort-Collaboration, the PLATO Collaboration and several previous studies on the safety of stopping OI prophylaxis.

This protocol is based on a relational structure (with some very minor deviations) and currently incorporates 26 data tables and numerous lookup-tables for the codes. It is evident that - depending on the questions addressed - only subsets of tables and fields will have to be extracted for data exchange.

We have not elaborated on database systems (e.g. SQL-Server, Oracle, Access) and their respective file formats as there are excellent tools for transferring data between most of the popular packages (e.g. ​StatTransfer). The suggested data structure should work with most formats and software packages.

Please keep in mind that the primary purpose of this document is to provide you with formats for data-exchange but not for an operational database used for data-management on a day-to-day basis. Some considerations with that respect can be found in the appendices.

We plan to update this document on a regular basis and the most recent versions will be made available on the HICDEP website. HICDEP is a format under constant improvement (currently under the EuroCoord Project, Grant Agreement No. 260694) and additions are made almost every year. Please refer to the ChangeLog for the most current updates and always use the tables available on the HICDEP website for most current coding lists for ART and MED drugs.

Members of EuroCoord WP4, September 2011