1. Research Unit; Complejo Hospitalario La Mancha Centro; Alcázar de San Juan Spain
2. Department of Gastroenterology; Hospital Universitario Central de Asturias; Oviedo Spain
3. Family and Community Medicine Teaching Unit; Escola Valenciana d’ Estudis de la Salut; Valencia Spain
4. Department of Gastroenterology; Hospital General de Tomelloso; Tomelloso Spain