[1] Vocat Univ Arnhem, Inst Primary Teacher Educ, Nijmegen, Netherlands
[2] Radboud Univ Nijmegen, Med Ctr, Dept Otorhinolaryngol, Nijmegen, Netherlands
[3] UZ Leuven, Dept Otorhinolaryngol Head & Neck Surg, Louvain, Belgium
[4] Katholieke Univ Leuven, Ctr Excellence Voice, Lab Exp ORL, Louvain, Belgium