Ciullo, S., Collins, A., Wissinger, D. R., McKenna, J. W., Lo, Y.-L., & Osman, D. (2020). Students with learning disabilities in the social studies: A meta-analysis of intervention research. Exceptional Children. https://doi.org/10.1177/0014402919893932.
Content-area classes such as social studies can present particular challenges for students with learning disabilities (LD). These classes require students to learn new information as well as new ways of thinking and reading text. As a result, it is important that researchers develop interventions that are specifically aimed at helping students with LD to succeed in content learning while also improving their reading skills. Ciullo and colleagues synthesized the results of 40 years of this line of research in an effort to determine if these interventions were effective for students with LD and whether particular characteristics of interventions were associated with larger effects.
Social studies instruction involves teaching students both domain-general and discipline-specific instruction. Domain-general instruction involves teaching students skills that they can use across the curriculum. These skills include reading comprehension, cognitive strategies such as mnemonics and graphic organizers for gaining content knowledge, and the use of digitized materials and alternative texts to make content available in forms that are easier for students with LD to access. Discipline-specific instruction pertains most directly to learning social studies by approaching the subject matter like a content expert. These approaches include critical thinking, inquiry-based learning, and engaging in argumentative writing to interpret controversial historical events. Previous research has focused primarily on domain-general skills interventions for students with LD. Ciullo and colleagues included both domain-general and discipline specific instruction in this review to provide a more comprehensive synthesis of the research on social studies interventions.
Studies were included in Ciullo et al.’s meta-analysis if at least 50% of the participants were students with LD in K–12 (or if effect sizes for students with LD from a larger study could be independently calculated), if the intervention focused on social studies, and if at least one of the study outcomes was a measure of social studies learning. Studies using experimental, quasi-experimental, and multiple-treatments designs were included. A total of 33 studies met these criteria and were included in the analysis. Nine other studies were included in the synthesis but not the meta-analysis because it involved a research design where students participated in more than one condition. Several study characteristics were examined to see if they produced effects that differed significantly in magnitude. These included whether the time period when the study was published (before 2005 or 2005–2017); grade level of student participants (K–8 or 9–12); whether a teacher or researcher implemented the intervention; the study’s research design (experimental or quasi-experimental); the size of the instructional group (less than six students or six or more students); and the number of sessions (less than 10 or 10 or more).
Typically, a meta-analysis of intervention studies reports results using a metric called an effect size. Effect sizes allow for the results of interventions to be compared across studies even when they use different tests to determine if the intervention students outperform students in the comparison condition. By converting results to effect sizes, results of all studies are transformed to be on the same scale. This scale is the number of standard deviation units (SDs) that differentiate the performance of students in the intervention and comparison groups at the end of the study.
Overall, the average effect size across studies was 0.76. None of the previously mentioned study characteristics (e.g., grade level, group size) assessed by Ciullo and colleagues were shown to make a significant difference in the average effect size of interventions. However, they describe general trends in the results.
Studies that focused on domain-general literacy skills (e.g., multicomponent reading comprehension interventions) and content learning strategies (e.g., graphic organizers, mnemonics) had large effects for students with LD. Effects were moderate in size in studies where the intervention involved providing alternate materials and/or digitized texts. For studies with a discipline-specific focus on reading/writing like a historian using primary sources, effects generally were small in magnitude.
Large effects were found for studies that focused on and measured reading comprehension skills and strategies. Smaller effects tended to be seen in studies where the intervention involved peer-mediated reading and where the focus was on reading skills specific to the social studies discipline.
When interventions assessed content learning, effects tended to be large. Reading measures that assessed reading of social studies materials had moderate-sized effects on average. Effects on measures that were developed by the study’s researchers and were proximal to the intervention tended to be larger than those from standardized measures.
Studies published in 2005 or later tended to have smaller effects compared to earlier studies, perhaps due to changes in standards for study design over time. Interventions focused on high school students showed somewhat larger effects than those for students in K–8. Additionally, studies with experimental designs had somewhat larger effects than quasi-experimental studies and those that met What Works Clearinghouse study quality standards (with or without reservations) had slightly larger effects than those that did not meet the standards. Finally, interventions implemented by researchers had effects that were somewhat larger than those implemented by teachers and shorter interventions (10 sessions or less) had somewhat larger effects than longer interventions. There was no difference in effect sizes based on whether studies involved less than 30 hours of intervention or 30 or more hours.
Interventions for students with LD that focused on social studies were quite effective in general. Social studies instructional time has been shortened in recent years to provide more time to focus on mathematics and reading instruction (Heafner & Fitchett, 2012). However, these results suggest time devoted to social studies instruction may benefit these students by improving their reading and content learning skills.
Intervention components such as graphic organizers, comprehension strategy instruction, and mnemonics were found to have strong effects. However, observational research has determined that teachers infrequently use these instructional approaches (e.g., Kent et al., 2018). More work must be done to bridge the research-to-practice gap so that students with LD have opportunities to learn and use these effective learning strategies.
Nearly 90% of the measures included in the meta-analysis were proximal to the intervention and researcher-developed. More research using standardized measures of reading and social studies are needed to determine if student gains are generalizing beyond the intervention’s context. These studies are needed among high school students in particular.