Background/aims: Approximately 50% of patients with functional dyspepsia have Helicobacter pylori infection; it remains controversial whether this infection causes chronic symptoms, but rigorously conducted therapeutic trials should establish whether H. pylori plays a role in functional dyspepsia. The aim here was to determine whether the trials published over the past 10 years were methodologically adequate to establish a role for this infection in functional dyspepsia.
Methods: A broad-based Medline search to identify all treatment trials published between 1984 and 1993 was performed. All functional dyspepsia trials were systematically analyzed for potential design strengths and weaknesses.
Results: Sixteen trials were included; 8 reported that anti-H. pylori therapy was efficacious and 8 failed to detect a statistically significant benefit. However, in all studies one or more serious methodological weakness was identified, including nonrandomized, non-placebo-controlled designs, lack of maintenance of blindness, application of inadequate outcome measures, failure to eradicate infection and follow up patients after therapy, and inadequate study power.
Conclusions: There is a pressing need for well-designed trials in H. pylori-positive dyspepsia, and practical suggestions are provided based on a review of the published literature.