A growing literature measures the impact of education interventions in low- and middle-income countries on both access and learning outcomes. But how should one contextualize the size of impacts? This article provides the distribution of standardized effect sizes on learning and access from 234 studies in low- and middle-income countries. We identify a median effect size of 0.10 standard deviations on learning and 0.07 standard deviations on access among randomized controlled trials. Effect sizes are similar for quasi-experimental studies. Effects are larger and demonstrate higher variance for small-scale studies than for large-scale studies. The distribution of existing effects can help researchers and policymakers to situate new findings within current knowledge and design new studies with sufficient statistical power to identify effects.

越来越多的文献衡量了低收入和中等收入国家的教育干预对获取和学习成果的影响。但是，我们应该如何将影响的大小与背景联系起来呢？本文提供了来自低收入和中等收入国家的 234 项研究的标准化效应量对学习和访问的分布。我们确定了随机对照试验中学习的 0.10 个标准差和 0.07 个标准差的中位效应大小。准实验研究的效应量相似。与大规模研究相比，小规模研究的效果更大，并且表现出更高的方差。现有影响的分布可以帮助研究人员和决策者将新发现置于现有知识中，并设计具有足够统计能力的新研究来识别影响。