Published online Dec 15, 2001. doi: 10.3748/wjg.v7.i6.801
Revised: September 19, 2001
Accepted: October 23, 2001
Published online: December 15, 2001
AIM: To follow the principles of evidence based medicine to reach the integrated results of these studies.
METHODS: Twenty-one papers of case-control studies were selected, including 11 on gastric cancer, 7 on precancerous lesion of stomach and 3 on lymphoma of stomach. Meta analysis was used to sum up the odds ratios (OR) of these studies.
RESULTS: H. pylori vsgastric cancer (intestinal and diffuse type): the odds ratio from the fixed effect model is 3.0016 (95% CI: 2.4197-3.7234, P < 0.001). H. pylori vs precancerous lesion of stomach: a random effect model was used to calculate the summary odds ratio and its value is 2.5635 (95% CI: 1.8477-3.5566, P < 0.01). H. pylori vs lymphoma of stomach: though the quantity of literature is too small to make Meta analysis, the data of these 3 studies show that lymphoma of stomach is highly associated with H. pylori infections.
CONCLUSION: Since it had been revealed that H. pylori infection pre-exists in gastric carcinoma and precancerous lesions, the results of Meta analysis present a strong evidence to support the conclusion that H. pylori infection is a risk factor for gastric carcinoma.