Investigators will be eligible for authorship if they contribute substantially to study planning, data collection, data analysis and interpretation, writing and critical review of the manuscripts. Two authors per centre will be included as main authors of each study. As a member of the Steering Committee, the local Representing Member will take any decisions on co-authorship related to his/her centre on the basis of the above criteria. Those researchers who plan a sub-study, interpret the analysis and write the article will be the first and last authors of the study. Analyses will be performed and/or monitored by an independent Central Core Statistic Laboratory. When an article is submitted to a journal with a maximum number of co-authors, the Steering Committee will decide on the authors on the basis of their contribution to the design of the study, data collection, interpretation of data, writing, and critical review of the paper.