“…Based on previous studies of the potential risk factors related to prolonged hospitalization, we collected the following information from the patients' medical records: age, gender, previous episodes, abdominal pain, GI bleeding, GI symptoms other than abdominal pain, fever, use of glucocorticoid before or on admission day, laboratory and urinalysis data, ultrasound findings, and the length of hospital stay. 4,6,7,[10][11][12][13] Gastrointestinal bleeding was defined as hematemesis, melena, hematochezia, or positive stool guaiac test. Stool guaiac test was conducted on a case-by-case basis.…”