MEDLINE was searched from 1983 onwards using the following keyword search strategies: 'pylori, ulcer, treatment', 'pylori, ulcer, eradication'; 'pylori, ulcer, recurrence'; 'pylori, double-blind'. An additional search was conducted with these keyword combinations, but substituting 'pyloridis' for 'pylori'. The reference lists of the identified articles, as well as other recent overviews of H. pylori therapy, were also examined.
Unpublished material were obtained by contacting pharmaceutical companies that manufacture medications used for H. pylori therapy in the USA (e.g. Abbott Laboratories, Astra Merck, Glaxo Wellcome, Procter and Gamble) and investigators in the field of H. pylori. The authors also reviewed open presentations made to the US Food and Drug Administration, and abstracts from annual meetings (1988 to 1996) of the American Gastroenterological Association, the American College of Gastroenterology, and the European Helicobacter pylori Study Group.