026 A COMPARISON OF SYSTEMATIC REVIEWS OF HELICOBACTER PYLORI ERADICATION FOR NON-ULCER DYSPEPSIA

J. Deeks, B. Delaney², D. Forman¹, P. Moayyedi². ICRF/NHS Centre for Statistics in Medicine, Oxford, UGPD Cochrane Group; ¹University of Leeds; ²Primary Care Sciences Building University of Birmingham, UK

Objectives: We have published a Cochrane systematic review on the efficacy of H. pylori eradication therapy in non-ulcer dyspepsia (NUD). We reported that this intervention had a statistically significant effect in curing dyspepsia symptoms. A US systematic review suggested there was no significant effect of H. pylori eradication therapy on NUD symptoms. We explored reasons for these discrepant results.

Results: We identified six differences in methodology. The US review included all dual, triple and quadruple H. pylori eradication therapies, searched until December 1999, did not contact authors, included abstracts, assumed drops outs were treatment failures and analysed results as odds ratio for cure. The Cochrane review included all therapies proven to successfully eradicate H. pylori, searched until May 2000, contacted authors, only included abstracts if further information was available, excluded drop-outs from the analysis and analysed results as relative risk of remaining dyspeptic. The influences these factors had on the conclusion of the review are outlined in table⇓. Excluding trials published in 2000 had a major impact on the results, reducing the number of trials in the review and widening 95% confidence intervals. Use of the odds ratio increased heterogeneity and a random effects model yielded a non-significant overall effect. Other differences in methodology did not make a difference in this instance.

Conclusions: The results of this review in a fast developing field depend on inclusion of all relevant articles. The ability to continually update Cochrane reviews ensures that they are the more appropriate format for publishing reviews in research areas that are fast evolving.

027 EFFECTS OF HELICOBACTER PYLORI EXTRACTS ON ENDOTHELIAL CELL PROLIFERATION AND MIGRATION IN VITRO

H.R. Pearce^{1 …}