A Meta-Analysis of the Effects of K–5 Expository Text Reading Interventions

• In Event: Understanding New Approaches to Early Language and Literacy Development

Abstract

Objectives
This study was to conduct a comprehensive meta-analysis to systematically evaluate and synthesize the effectiveness of K-5 literacy interventions that used informational (or nonfiction) texts. Specifically, we explored (a) what interventions were effective on what outcomes, (b) for whom (e.g., multilingual learners, students with disabilities), and (c) under what circumstances (e.g., instructional approaches).

Rationale
Although proficient informational text comprehension is critical for students’ disciplinary learning and academic success (Martin & Duke, 2010), many elementary-grade students struggle to read and write challenging and complex informational texts with high knowledge demands independently (National Center for Education Statistics, 2019). This struggle may be due to limited exposure to informational texts with disciplinary content and overemphasis on word decoding skills and the use of narrative fiction texts in primary-grade classrooms (Duke & Block, 2012).
Reading and comprehending expository text require different skill sets than those needed to comprehend narrative text (Meyer, 1975). Expository text comprehension requires students to make inferences, integrate background knowledge with new information from text, and use domain-specific vocabulary and text structure knowledge that are not commonly needed in narrative texts (Snow, 2002). As these complex tasks increase cognitive demands, students can benefit from effective expository text comprehension interventions. It is important to conduct a rigorous meta-analysis of contemporary research to determine whether expository text comprehension instruction is effective for improving learning outcomes and to identify specific instructional principles and practices with evidence of effectiveness.

Methods
We used a quantitative research method to synthesize existing study results. We first completed electronic reference database searches using different combinations of search terms (e.g., intervention, expository text) to identify qualifying studies published in academic journals between 1970 and 2022. Second, we used several criteria to select studies to be included (e.g., quasi-experiment design) and excluded. Third, we created a codebook to record all pertinent information on studies. The methodological quality of studies was evaluated using a risk-of-bias tool. Finally, statistical analyses were performed to answer the three research questions.

Results
We identified 28 studies that compared K-5 reading interventions to a control condition. Findings revealed that expository text reading interventions resulted in positive, statistically significant changes in vocabulary knowledge and reading comprehension outcomes with small to moderate effect sizes. Large effect sizes were found when researcher-developed assessments were used. We did not find evidence of adverse effects on foundational word reading skills. We identified two moderators that led to increased effect sizes: students with disabilities and instructional dosage.

Scholarly Significance of the Study
The results support expository text reading instruction for elementary-aged students. This meta-analysis provided important insight into the strengths and weaknesses of the studies examining the effectiveness of expository text reading instruction for improving students’ vocabulary and reading comprehension. The results provide not only guidelines for program developers but also instructional implications for elementary teachers that can potentially improve the quality of their expository text reading instruction. This review also calls for more longitudinal intervention research that investigates how positive treatment impacts can be sustained over time.

Authors

• Jackie Eunjung Relyea, North Carolina State University
  Presenting Author

• HyeJin Hwang, University of Minnesota
  Non-Presenting Author

• Dennis S. Davis, North Carolina State University
  Non-Presenting Author

• Katie Peachey, North Carolina State University
  Non-Presenting Author

• Courtney Weathers, North Carolina State University
  Non-Presenting Author