[1] Univ Bern, Inst Social & Prevent Med, Mittelstr 43, CH-3012 Bern, Switzerland
[2] Univ Basel, Univ Childrens Hosp Basel, Dept Neuropediatr & Dev Med, Basel, Switzerland
[3] Univ Bern, Univ Hosp Bern, Univ Childrens Hosp,Inselspital, Dept Neuropediatr Dev & Rehabil, Bern, Switzerland
[4] Univ Bern, Univ Hosp Bern, Dept Anaesthesiol & Pain Med, Inselspital, Bern, Switzerland
[5] Bahnhof Apotheke Langnau AG, Langnau, Switzerland
[6] Univ Bristol, Bristol Med Sch, Populat Hlth Sci, Bristol, England