Inadequacy of the literature on the relationship between drugs, ulcers, and gastrointestinal bleeding.
D003430:Cross-Sectional Studies; D064420:Drug-Related Side Effects and Adverse Reactions; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced*; D006801:Humans; D010437:Peptic Ulcer / Q000139:chemically induced*; D010506:Periodicals as Topic; D012107:Research Design; D013223:Statistics as Topic; D013997:Time Factors