We evaluate the direct and inferential mediation (DIME) model for reading comprehension with a sample of struggling readers in Grades 3 to 5 (N = 364) in the context of a large-scale randomized controlled trial (RCT) investigating two theoretically distinct reading interventions (text processing + foundational skills [n = 117] or text processing only [n = 120]) and a control condition (n = 127). We investigate whether the intervention affects not just reading comprehension levels, but also how variables within the reading system interrelate. This approach allows the focus to shift from intervention as influencing a change in reading comprehension status to a complex set of processes. We fit structural equation models (SEMs) to evaluate the DIME model at baseline, and a change model including reading comprehension and word reading at posttest. There were no significant mean differences between groups in reading comprehension. However, significant differences emerged on the direct and indirect effects of background knowledge, vocabulary, word reading, strategies, and inferencing on comprehension across grade levels and treatment conditions. Related to treatment groups, background knowledge, vocabulary, and inferencing were significantly related to comprehension at posttest for students who received text processing and/or foundational skills interventions. The results have implications for the direct instruction of higher-order reading skills in the context of multicomponent interventions.

我们在一项大规模随机对照试验 (RCT) 的背景下，以 3 至 5 年级阅读困难的样本 ( N = 364) 为样本，评估了用于阅读理解的直接和推理中介 (DIME) 模型，该试验调查了两种理论上不同的阅读干预措施（文本处理 + 基础技能 [ n = 117] 或仅文本处理 [ n = 120]）和控制条件（ n = 127）。我们研究干预是否不仅影响阅读理解水平，还影响阅读系统内的变量如何相互关联。这种方法允许重点从影响阅读理解状态变化的干预转移到一组复杂的过程。我们拟合结构方程模型（SEM）来评估基线时的 DIME 模型，以及包括后测时的阅读理解和单词阅读的变化模型。各组之间的阅读理解能力没有显着的平均差异。然而，背景知识、词汇、单词阅读、策略和推理对不同年级和治疗条件的理解的直接和间接影响出现了显着差异。与治疗组相关，接受文本处理和/或基础技能干预的学生的背景知识、词汇和推理与后测理解力显着相关。研究结果对于在多成分干预的背景下直接指导高阶阅读技能具有重要意义。