This study investigates whether prior knowledge indirectly affects intertextual comprehension performance through its effect on intratextual comprehension. The secondary data analysis used raw data from extant studies, all of which assessed these three aspects of multiple text comprehension (i.e., prior knowledge, intratextual comprehension, and intertextual comprehension). The results demonstrated that prior knowledge was a positive predictor of readers' abilities to integrate information across multiple texts, with this effect mediated by intratextual comprehension performance. Further, the mediated effect of prior knowledge on intertextual comprehension via intratextual comprehension was weaker when the measures reflected readers' ability to reproduce integrated ideas within and across reader-generated essays than when they reflected readers' abilities to recognize linkages among ideas distributed across multiple texts. The results uniquely contribute to the understanding of the complex relationship between individual differences and multiple text comprehension, with particular insights that this relationship may depend on the outcome measures that are used.

Educational Relevance Statement

Prior knowledge has both a direct and an indirect influence on intertextual comprehension, with the latter mediated through intratextual comprehension. Moreover, the strength of this indirect influence depends on whether the comprehension measures required that readers identify or recreate valid inferences linking information within and across texts. The findings expand on understandings of the mechanisms involved in constructing integrated understandings from both single texts and multiple texts, and thus inform practitioners in the field. By recognizing the critical role of students' prior knowledge in comprehending both single and multiple texts, teachers can facilitate the learning process by developing more effective teaching strategies that underlie prior knowledge in intra- and inter-textual comprehension.