Towards better meta-analyses in assisted reproductive technology: Fixed, random or multivariate models?

摘要

AIM: To study the validity of the fixed, random, and multivariate meta-analytical models applied in meta-analyses in artificial reproduction technique. METHODS: Based on common characteristics of in vitro fertilization(IVF) meta-analyses, we simulated a large number of data to compare results issued from the fixed model(FM) with the random model(RM). For multiple endpoints meta-analysis(MA), we compared the univariate RM with the multivariate model(MM). Finally, we illustrate our findings in re-analyzing a recent MA. RESULTS: In our review, although a homogeneous effect was excluded in 89% of the MAs(11%), FM was utilized in 41 studies(82%). From simulations, a concordance of 59% ± 6% was found between the two tests, with up to 65% of falsely significant results with FM. The Q-test on studies characterized by substantial heterogeneity falsely accepted homogeneity in 46% of studies. Comparing separate univariate RM and MM on multiple endpoints studies, MM reduces the between endpoint discrepancy(BED) of 68%, and increases the power of 57% ± 8%. In the example dealing with the controversial effect of luteneizing hormone supplementation to follicle stimulating hormone during ovarian stimulation in IVF cycles, MM reduced BED by 66%, and consistent effects were found for all the endpoints, irrespective of partial reporting. CONCLUSION: The FM generally may produce falsely significant differences. The RM should always be used. For multiple endpoints, the MM constitutes the best option.