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Honoring Uncontrolled Events: Commentary on Slocum et al.


In this special section of Perspectives on Behavior Science, Slocum et al. (2022) provide a summary of the logic and protocol for the construction, implementation, and analysis of single-case multiple-baseline designs. A major contribution of this article is a reassessment of the nonconcurrent multiple baseline design as a credible approach to documenting experimental control. In this commentary we provide considerations for readers as they approach the Slocum et al. article and suggest that although the resurrection of nonconcurrent multiple-baseline designs to a higher status is warranted, researchers will find more control for threats to internal validity in concurrent multiple-baseline designs, and the concurrent format should remain the preferred option.

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The authors acknowledge and extend appreciation to Dr. Thomas R. Kratochwill for his comments on early drafts of this commentary.

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Correspondence to Robert H. Horner.

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Horner, R.H., Machalicek, W. Honoring Uncontrolled Events: Commentary on Slocum et al.. Perspect Behav Sci (2022).

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  • single-case design
  • multiple-baseline design
  • concurrent
  • nonconcurrent
  • internal validity