Assessment & Research

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

Wolfe et al. (2019) · Behavior Analysis in Practice 2019
★ The Verdict

A simple five-step checklist turns visual inspection into a number you can write in the session note.

✓ Read this if BCBAs who review A-B-A-B or multiple-baseline graphs by hand in clinic or school settings.
✗ Skip if BCBAs already using automated R packages like RDARBS for graphing and stats.

01Research in Context

01

What this study did

Wolfe et al. (2019) wrote a how-to paper for BCBAs. They give step-by-step rules for looking at A-B-A-B or multiple-baseline graphs. You follow the steps and get a number that tells you if the intervention worked.

The authors tested the rules on a few graphs in a small pilot. They did not collect new behavior data.

02

What they found

The protocol gives a clear score for level, trend, and overlap. The score helps you decide yes or no: an effect is there or it is not.

The pilot showed the rules can be used quickly, but the paper does not report hit rates or reliability numbers.

03

How this fits with other research

Manolov et al. (2017) came first and showed free R tools that draw graphs and run stats. Wolfe et al. (2019) add a paper checklist for people who prefer to eyeball first.

Ruiz et al. (2025) now supersedes both: their RDARBS R package draws the graph and scores it in under a minute. You can still use Wolfe’s rules if you want to double-check by hand.

Kril et al. (2022) tested a short decision algorithm with students and found it boosted accuracy. Their classroom data extend Wolfe’s idea from paper to real training.

04

Why it matters

If you run single-case sessions and hate statistical software, print the Wolfe checklist. Work through the five questions while you look at today’s graph. You will leave supervision with a number you can defend in your notes or to parents.

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→ Action — try this Monday

Tape the Wolfe checklist next to your desk and score today’s graph before writing your summary.

02At a glance

Intervention
not applicable
Design
methodology paper
Finding
not reported

03Original abstract

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.

Behavior Analysis in Practice, 2019 · doi:10.1007/s40617-019-00336-7