EVENTS

Seminar: Empirical priors for the between-study variance in meta-analyses (Eleanor Pullenayegum)

Seminar

Department of Statistics

Thursday, 22 October 2009 at 3:30PM

Sidney Smith Hall, Room 1086

Empirical priors for the between-study variance in meta-analyses

Professor Eleanor Pullenayegum

McMaster University

It is well known that when a Bayesian meta-analysis includes a small number of studies, inference can be sensitive to the choice of prior for the between-study variance. Choosing a vague prior does not solve the problem, as inferences can be substantially different depending on the degree of vagueness. Moreover, because the data provide little information on between-study heterogeneity, posterior inferences for the between-study variance based on vague priors will tend to be unrealistic. It is thus preferable to adopt a reasonable, informed prior for the between-study variance. However, relatively little is known about what constitutes a realistic distribution. Based on data from the Cochrane Database of Systematic Reviews, this talk will describe the distribution of between-study variance in published meta-analyses, and propose some realistic informed priors for use in meta-analyses of binary outcomes. It is hoped that these priors will improve the calibration of inferences from Bayesian meta-analyses.