BAYESIAN-APPROACH FOR METAANALYSIS OF CONTROLLED CLINICAL-TRIALS

A new method to perform meta-analysis of controlled clinical trials with binary response variable is developed using a Bayesian approach. It consists of three parts: (1) For each trial, the risk difference (the proportion of successes in the treated group minus the proportion of successes in the control group) is estimated; (2) The homogeneity of the risk difference among the different trials is tested; and (3) The hypothesis - the effect of the treatment for the homogeneous pool of trials is greater than or equal to a given fixed constant - is tested. The performance of the Bayesian procedure to test the homogeneity of the risk difference among trials is compared with the chi-square test proposed by DerSimonian and Laird (Controlled Clinical Trials 7, 177-188, 1986) by means of pseudo-random simulation. The conclusion was that the Bayes test is more reliable, either in its exact or asymptotic versions, since it makes fewer decision errors than the chi-square test. As an illustration, the Bayesian method is applied to data of chemotherapeutic prophylaxis of superficial bladder cancer.