Author contributions
The authors’ contributions were as follows – M.D.T., M.T. conceptualized the study and defined the analytical strategy; F.S.E.: performed statistical analyses; M.D.T. supervised statistical analyses and drafted the manuscript; M.T.: supervised statistical analyses and writing; F.S.E., N.D.P., Y.E., J.A., P.G., S.H., G.S., M.Z., E.W., X.dL, F.C., M.T., SAPRIS-SERO study group: played a key role in the acquisition of the data. All authors critically helped in the interpretation of results, revised the manuscript and provided relevant intellectual input. They all read and approved the final manuscript. M.D.T. and M.T. had primary responsibility for the final content.