Eysenck H J
Institute of Psychiatry, London.
BMJ. 1994 Sep 24;309(6957):789-92. doi: 10.1136/bmj.309.6957.789.
Including all relevant material--good, bad, and indifferent--in meta-analysis admits the subjective judgments that meta-analysis was designed to avoid. Several problems arise in meta-analysis: regressions are often non-linear; effects are often multivariate rather than univariate; coverage can be restricted; bad studies may be included; the data summarised may not be homogeneous; grouping different causal factors may lead to meaningless estimates of effects; and the theory-directed approach may obscure discrepancies. Meta-analysis may not be the one best method for studying the diversity of fields for which it has been used.
在荟萃分析中纳入所有相关材料——好的、坏的和一般的——会承认荟萃分析旨在避免的主观判断。荟萃分析中会出现几个问题：回归通常是非线性的；效应通常是多变量而非单变量的；覆盖范围可能有限；可能会纳入质量差的研究；汇总的数据可能不是同质的；将不同的因果因素分组可能会导致对效应的无意义估计；而且理论导向的方法可能会掩盖差异。荟萃分析可能不是研究其应用领域多样性的最佳方法。
