OBJECTIVETo study the center effect discrepancy in the multi-center clinical trials.

METHODSTwo groups of data collected from the multi-center clinical trials were used. Data were processed by covariance analysis and Meta-analysis.

RESULTSIn the covariance analysis, the discrepancy of the center effect values indicated statistical significance. Through Meta-analysis on fixed effect model, the discrepancy in one heterogeneity test showed no statistical significance (P > 0.05) while the inter-group discrepancy of the merged effect values drawn from analysis based on fixed effect model having statistical significance (P < 0.05). In the random effect model, the discrepancy in one heterogeneity test showed statistical significance (P < 0.05) while the inter-group discrepancy of the merged effect values drawn from analysis based on random effect model having no statistical significance (P > 0.05).

CONCLUSIONSStudies on multi-center random controlled clinical trials, when statistical significance was found in the interaction discrepancy between the inter-center and the center-group relation, the merged effect values should be compared and analyzed by an appropriate statistic model based on the heterogeneous test results from the Meta-analysis. However, if the result from covariance analysis and the one from Meta-analysis did not agree to each other, the results drawn from the Meta-analysis were reliable.