Abstract
Mediation analysis in Single Case Experimental Designs (SCEDs) evaluates intervention mechanisms for individuals. Despite recent methodological developments, no clear guidelines exist for maximizing power to detect the indirect effect in SCEDs. This study compares frequentist and Bayesian methods, determining (1) minimum required sample size to detect indirect effects in AB designs, (2) relative power for proximal vs. distal mediators, and (3) optimal observation allocation between baseline and treatment phases. Simulation study results suggest highest power for proximal mediators with at least 60 observations evenly allocated to A and B phases. Findings from this study have important implications for the design and statistical analysis in numerous fields that routinely employ SCEDs, ranging from education to psychology and nursing.
| Original language | English |
|---|---|
| Pages (from-to) | 149-166 |
| Number of pages | 18 |
| Journal | The Journal of Experimental Education |
| Volume | 93 |
| Issue number | 1 |
| Early online date | Aug 2023 |
| DOIs | |
| Publication status | Published - 2025 |
Bibliographical note
Publisher Copyright:© 2023 Taylor & Francis Group, LLC.
Funding
This work was supported by Institute of Education Sciences (grant number R305D190022 awarded to Dr. Moeyaert) and the Social Sciences and Humanities Research Council (Insight grant number 256438 awarded to Dr. Miočević).
Keywords
- AB-design
- SCEDs
- mediation analysis
- power
- simulation study