Author contributions
All authors had access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. MG, HH, LM, OT, KAB, and WM contributed to the study conception and design of the analysis. MG, HH, TD, EVC, and WM were responsible for data acquisition. Statistical analysis was performed by LM. Study supervision was done by MG, KAB, LM, and WM. The first draft of the manuscript was written by MG and WM, and all authors provided critical review of the manuscript for important intellectual content. All authors read and approved the final manuscript.