random effects model
In a meta-analysis, a statistical model in which both the within-study variance and the between-studies variances are included in the assessment of the degree of uncertainty (confidence interval) of the combined effect of the studies.
Note: If there is significant heterogeneity among the results of the studies included in a meta-analysis, a random effects model will give wider confidence intervals than a fixed-effect model.
(Related concepts: fixed-effect model)