Using a Systematic Review to Explore Single-Subject Design Use Within Special Education Over Time

Abstract

While teachers and researchers of students with disability are commonly interested in individual students and their progress towards individualised goals, traditional approaches to educational research that aim to illustrate generalisation between cause and effect are still commonly used. Traditional approaches, such as group-comparison designs, are used to demonstrate improved performance for the average student; however, they also obscure individual student data. Within special and inclusive education, single-subject designs may provide more appropriate conclusions to particular types of questions than traditional research methods as they allow for the examination of a functional relationship between the dependent and independent variables and rely on the participant serving as their own control. This article provides a summary of the use of single-subject designs within the field of special education over time and the findings of a systematic review conducted according to the PRISMA statement are presented. Through this systematic review, published articles from 7 prominent special education journals that involved intervention for school-aged students with disability were examined. In addition, a sample of exemplar studies that have employed single-subject designs are discussed.

Prevalence of Research Design in Special Education: A Survey of Peer-Reviewed Journals

“…The disparities in design rates across journal types are consistent with the evidence provided in previous reviews (e.g., Zanuttini, 2020). The prevalence of single-case designs across journals for students with EBD, relative to qualitative or group designs, is potentially problematic.…”

“…Nonetheless, our results in regard to the high prevalence of descriptive-correlational studies, the continued decline of commentary (i.e., 42% of articles published between 1988 and 2006, compared with 24.67% more recently), and the scarcity of qualitative work are generally consistent with earlier work (Mastropieri et al, 2009). Our findings also suggest that single-case designs represent a higher proportion of experimental studies than previously indicated (e.g., Zanuttini, 2020), with a similar pattern observed in cross-categorical journals. However, cross-categorical journals included an outlier with a high number of single-case designs (i.e., Journal of Behavioral Education ; see Table 1), suggesting single-case design is concentrated in journals dedicated to people with developmental disabilities and EBD.…”

“…The rate of published empirical studies and intervention work increased over time; however, the authors did not report design-specific information for journal categories. Zanuttini’s (2020) review of seven journals concerning various disability categories focused on experimental research published between 2014 and 2019 and found that single-case designs represented 45% of experimental studies, with clear discrepancies based on the categorical emphasis of each journal. Specifically, journals for students with emotional/behavioral disorders (EBD) published higher proportions of single-case designs than journals for students with LD or cross-categorical journals.…”

“…Thus, this study examines the prevalence of research designs in special education journals. Given that previous studies have linked types of research to specific categories (e.g., single-case designs and EBD; Zanuttini, 2020), we target cross-categorical special education journals—those with the highest impact factors that address a range of issues and disabilities—as well as publications related to developmental disabilities, EBD, and LD. The following were the research questions:…”

Using a tablet-mediated intervention for teaching pre-addition skills to children with autism

“…Single subject designs enable comparisons between participants, behaviors, or environments, and the intervention is methodically managed via repeatable data collection. Single-subject designs repeated data points (typically taken prior to intervention to establish a baseline) are followed by a series taken during intervention, and in the final phase generalization and maintenance may provide more appropriate conclusions to particular types of questions in special and inclusive education [42]. To strengthen internal and external validity, the study must be duplicated across people, behaviors, and contexts (one of these three things) if a meaningful change results from the intervention.…”