[1] Tech Univ Munich, Chair Prevent Pediat, Munich, Germany
[2] St Justine Univ Hosp Res Ctr, Res Ctr, Montreal, PQ, Canada
[3] Univ Montreal, Dept Pediat, Montreal, PQ, Canada
[4] INRS Armand Frappier Inst, Epidemiol & Biostat Unit, Laval, PQ, Canada
[5] Univ Montreal, Dept Kinesiol, Montreal, PQ, Canada