Systematic Protocols for the Visual Analysis of Single-Case Research Data

Researchers in applied behavior analysis and related fields such as special education and school psychology use single-case designs to evaluate causal relations between variables and to evaluate the effectiveness of interventions. Visual analysis is the primary method by which single-case research data are analyzed; however, research suggests that visual analysis may be unreliable. In the absence of specific guidelines to operationalize the process of visual analysis, it is likely to be influenced by idiosyncratic factors and individual variability. To address this gap, we developed systematic, responsive protocols for the visual analysis of A-B-A-B and multiple-baseline designs. The protocols guide the analyst through the process of visual analysis and synthesize responses into a numeric score. In this paper, we describe the content of the protocols, illustrate their application to 2 graphs, and describe a small-scale evaluation study. We also describe considerations and future directions for the development and evaluation of the protocols.