1. Vodafone Foundation Institute and Chair for Children's Pain Therapy and Paediatric Palliative Care, Witten/Herdecke University, Datteln, Germany
2. Center for Child Neurology, Witten/Herdecke University, Datteln, Germany
3. Department of Pain Management, Ruhr University Bochum, Berufsgenossenschaftliche Universitätsklinik Bergmannsheil GmbH, Bochum, Germany
4. Department of Neurophysiology, Center of Biomedicine and Medical Technology Mannheim (CBTM), University of Heidelberg, Heidelberg, Germany