Prospective validation of the Glasgow Blatchford scoring system in patients with upper gastrointestinal bleeding in the emergency department - KÖKSAL, Özlem; ÖZEREN, Gülden; ÖZDEMİR, Fatma; ARMAĞAN, Erol; AYDIN, Şule; AYYILDIZ, Talat (Turkish Journal of Gastroenterology, 2012)