Accuracy of ICD-9 codes in identifying patients with peptic ulcer and gastrointestinal hemorrhage in the regional healthcare administrative database of Umbria.

by Massimiliano Orso, Iosief Abraha, Anna Mengoni, Fabrizio Taborchi, Marcello De Giorgi, David Franchini, Paolo Eusebi, Anna Julia Heymann, Alessandro Montedori, Giuseppe Ambrosio, Francesco Cozzolino
Published 2020-01-01