Using Single-Case Designs in Practical Settings: Is Within-Subject Replication Always Necessary?
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Behavior analysts have widely adopted and embraced within-subject replication through the use of reversal and multielement designs. However, the withdrawal of treatment, which is central to these designs, may not be desirable, feasible, or even ethical in practical settings. To examine this issue, we extracted 501 ABAB graphs from theses and dissertations to examine to what extent we would have reached correct or incorrect conclusions if we had based our analysis on the initial AB component only. In our first experiment, we examined the proportion of datasets for which the results of the first AB component matched the results of the subsequent phase reversals. In our second experiment, we calculated three effect size estimates for the same datasets to examine whether these measures could predict the relevance of conducting a within-subject replication. Our analyses indicated that the initial effects were successfully replicated at least once in approximately 85% of the cases and that effect size may predict the probability of within-subject replication. Overall, our results support the rather controversial proposition that it may be possible to set threshold values of effect size above which conducting a replication could be considered unnecessary. That said, more research is needed to confirm and examine the generalizability of these results prior to recommending changes in practice.
KeywordsAB design Effect size Error rate Replication Single-case design
This research project was supported in part by a salary award (no. 30827) and a grant (no. 32612) from the Fonds de Recherche du Québec—Santé as well as a grant from the Canadian Institutes of Health Research (no. 136895) to the first author.
- Ferron, J. M., & Levin, J. R. (2014). Single-case permutation and randomization statistical tests: present status, promising new developments. In T. R. Kratochwill & J. R. Levin (Eds.), Single-case intervention research: methodological and statistical advances (pp. 153–183). Washington, DC: American Psychological Association. https://doi.org/10.1037/14376-006.CrossRefGoogle Scholar
- Kazdin, A. E. (2011). Single-case research designs (2nd ed.). New York: Oxford University Press.Google Scholar
- Kratochwill, T. R., Hitchcock, J., Horner, R. H., Levin, J. R., Odom, S. L., Rindskopf, D. M., &Shadish, W. R. (2010). Single-case designs technical documentation. Retrieved from http://files.eric.ed.gov/fulltext/ED510743.pdf
- Levin, J. R., Ferron, J. M., & Kratochwill, T. R. (2012). Nonparametric statistical tests for single-case systematic and randomized ABAB… AB and alternating treatment intervention designs: new developments, new directions. Journal of School Psychology, 50, 599–624. https://doi.org/10.1016/j.jsp.2012.05.001.CrossRefGoogle Scholar
- Marquis, J. G., Horner, R. H., Carr, E. G., Turnbull, A. P., Thompson, M., Behrens, G. A., et al. (2000). A meta-analysis of positive behavior support. In R. Gersten, E. P. Schiller, & S. Vaughn (Eds.), Contemporary special education research: syntheses of knowledge base on critical instructional issues (pp. 137–178). Mahwah: Erlbaum.Google Scholar
- Novotny, M. A., Sharp, K. J., Rapp, J. T., Jelinski, J. D., Lood, E. A., & Steffes, A. K. (2014). False positives with visual analysis for nonconcurrent multiple baseline designs and ABAB designs: preliminary findings. Research in Autism Spectrum Disorders, 8, 933–943. https://doi.org/10.1016/j.rasd.2014.04.009.CrossRefGoogle Scholar
- Ombudsman Ontatrio. (2016). Nowhere to turn: investigation into the Ministry of Community and Social Services’ response to situations of crisis involving adults with developmental disabilities Retrieved from https://www.ombudsman.on.ca/Files/sitemedia/Documents/NTT-Final-EN-w-cover.pdf
- Pustejovsky, J. E. (2016, November 3). What is Tau-U? Retrieved from http://jepusto.github.io/What-is-Tau-U
- Québec Ombudsman. (2012). Services provided to young people and adults with a pervasive developmental disorder. Retrieved from https://protecteurducitoyen.qc.ca/sites/default/files/pdf/rapports_speciaux/2012-05-23_rapport_ted_2_EN.pdf
- Rohatgi, A. (2017). Plot Digitizer [computer software]. Retrieved from http://arohatgi.info/WebPlotDigitizer/app/
- Skinner, B. F. (1991). The behavior of organisms: an experimental analysis. Acton: Copley Publishing Group (Original work published 1938).Google Scholar