1. Universitat Rovira i Virgili, Carretera de Valls, 43007 Tarragona, Spain
2. Chair in Pediatric Pain, Unit for the Study and Treatment of Pain—ALGOS, Department of Psychology, Research Center for Behavior Assessment (CRAMC), 43007 Tarragona, Spain
3. Department of Anesthesia, McGill University, 1001 Boul. Decarie, Montreal, QC H4A 3J1, Canada
4. Xarxa Social i Sanitària, 43003 Tarragona, Spain
5. School of Medicine, Universitat Rovira i Virgili, IISPV, 43201 Reus, Spain
6. Department of Pediatrics, Hospital Universitari Sant Joan, Avgda. Dr. Josep Laporte 2, 43204 Reus, Spain
7. Pediatric Anesthesiology Service, Hospital Universitario La Paz, P. Castellana 261, 28046 Madrid, Spain