Authors’ contributions {31b}
AD
The investigators will together write the papers (including this protocol) with the principal investigator taken the lead. He will involve all co-investigators in the process. No use is or will be made of professional writers. AD is the principle investigator; he conceived the study and led the proposal and protocol development; CJvD, MN, MvV, CK, and AS contributed to study design and to the development of the proposal; EO is the lead study methodologist. All authors drafted and revised and approved the final manuscript.