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Tau-U/Evidence
Method evidence record

Tau-U

Tau-U is a rank-based effect-size index for single-case research that combines the degree of nonoverlap between baseline and treatment phases with the trend within phases, and that can optionally subtract out any improving trend already present in the baseline. Developed by Richard Parker, Kimberly Vannest, and colleagues in 2011, it extends the Nonoverlap of All Pairs (NAP) statistic by adding a Kendall-style trend component, giving practitioners a single index that is robust to outliers, has a known sampling distribution for significance testing, and does not unfairly credit a treatment for change that the baseline was already heading toward.

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Source record

Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.

Tau-U Nonoverlap Effect Size for Single-Case Research
Taxonomic method record · process-pipeline / social-work
  • Parker, R. I., Vannest, K. J., Davis, J. L., & Sauber, S. B. (2011). Combining nonoverlap and trend for single-case research: Tau-U. Behavior Therapy, 42(2), 284–299. · DOI 10.1016/j.beth.2010.08.006
  • Parker, R. I., & Vannest, K. J. (2009). An improved effect size for single-case research: Nonoverlap of all pairs. Behavior Therapy, 40(4), 357–367. · DOI 10.1016/j.beth.2008.10.006
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Related methods

Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.

Taxonomic bucketNonoverlap of All Pairsmachine-suggested · Relational suggestion, not evidence.Taxonomic bucketPercentage of Nonoverlapping Datamachine-suggested · Relational suggestion, not evidence.Same method familySingle-System Designmachine-suggested · Relational suggestion, not evidence.Same method familyVisual Analysis of Single-Case Datamachine-suggested · Relational suggestion, not evidence.

Evidence status

Sources recorded, not reviewed

Bibliographic sources are present. Claim-level evidence review has not been performed.

Sources

2 recorded citations, copied from the method source record.

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