Some general points in estimating heterogeneity variance with the DerSimonian-Laird estimator.
نویسندگان
چکیده
In this paper we consider estimating heterogeneity variance with the DerSimonian-Laird (DSL) estimator as typically used in meta-analysis. In its general form the DSL estimator requires inverse population-averaged study-specific variances as weights, in which case the estimator is unbiased. It has become common practice, however, to use estimates of the study-specific variances instead of their population-averaged versions. This can lead to considerable bias. Simulations illustrate these findings.
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ورودعنوان ژورنال:
- Biostatistics
دوره 3 4 شماره
صفحات -
تاریخ انتشار 2002