Contributors
MP, FV and AL had full access to all of the data in the study and MP took responsibility for the integrity of the data and the accuracy of the data analysis. MP and FV designed the study, wrote the study protocol and obtained the funding for the study. MP is the coordinator-investigator and FV the methodologist and supervisor. MP and FV were responsible for acquisition of data. MP, FV and AL were responsible for the verification of the underlying data, the analysis and the interpretation of data. AL was responsible for statistical analysis. MP and FV wrote the draft manuscript. MP, AL, IDC, DG, PML, and FV revised the manuscript and approved the final version before submission. MP was responsible for study supervision and was the guarantor for the study. All listed authors meet authorship criteria. All authors confirm that they had full access to all data in the study and accept responsibility for publication.