[1] Univ Witten Herdecke, Clin Children & Adolescents Datteln, Vodafone Fdn, Inst Childrens Pain Therapy & Palliat Care, D-45711 Datteln, Germany
[2] Royal Childrens Hosp, Dept Paediat Anaesthesia & Pain Management, Melbourne, Vic, Australia
[3] Univ Melbourne, Univ Dept Paediat, Murdoch Childrens Res Inst, Melbourne, Vic 3010, Australia
[4] Univ Appl Sci, Dept Social Sci & Cultural Studies, Dusseldorf, Germany
[5] Ruhr Univ Bochum, Dept Psychol Clin Psychol & Psychotherapy, Bochum, Germany
[6] Univ Hosp Munster, Dept Pediat Oncol, Munster, Germany