1. CINTESIS – Center for Health Technology and Services Research, Porto, Portugal
2. Grupo de Estudo da Doença Inflamatória Intestinal (GEDII), Porto, Portugal
3. Centro Hospitalar de São João, Gastroenterology Department, Porto, Portugal
4. Department of Biomedicine, Unit of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro 420-319 Porto, Portugal
5. Centro Hospitalar Lisboa Norte, Hospital Santa Maria, Gastroenterology Department, Lisboa, Portugal
6. Centro Hospitalar Universitário de Coimbra, Gastroenterology Department, Coimbra, Portugal
7. Centro Hospitalar Tondela e Viseu, Gastroenterology Department, Viseu, Portugal
8. Centro Hospitalar do Porto, Hospital Geral Santo António, Gastroenterology Department, Porto, Portugal
9. Department of Community Medicine, Information and Health Decision Sciences, Faculty of Medicine of the University of Porto, Portugal