 Fixed-effect meta-analysis

A common-effect synthesis treats study estimates as estimates of one shared effect. For independent approximately unbiased estimates $y_i$ with variances $v_i$, use $\hat{\mu }={\sum }_i{w}_i{y}_i/{\sum }_i{w}_i$ with $w_i=v_i^{-1}$. This model does not accommodate additional between-study heterogeneity.