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Estimating and testing mediation and moderation in within-subject designs
C M Judd1, D A Kenny, G H McClelland
1Department of Psychology, University of Colorado at Boulder, Colorado 80309-0345, USA. charles.judd@colorado.edu
Psychological Methods
|June 20, 2001
Summary
This study introduces new methods for analyzing treatment effects when the treatment is applied within individuals. It provides a way to understand the processes and factors influencing treatment outcomes in within-participant designs.
Area of Science:
- Psychology
- Quantitative Psychology
- Behavioral Research
Background:
- Mediation and moderation analyses are crucial for understanding treatment effects in psychological research.
- Existing analytical methods are well-established for between-participant treatment designs.
- Systematic procedures for mediation and moderation in within-participant treatment designs are lacking.
Purpose of the Study:
- To develop and present a novel analytic approach for examining mediation and moderation in within-participant treatment designs.
- To address the gap in systematic procedures for analyzing complex treatment effects in this specific research context.
Main Methods:
- The study proposes an analytical framework utilizing ordinary least squares (OLS) estimation.
- The approach is designed to handle situations where treatment effects vary within individual participants.
Main Results:
- The presented analytic approach provides a systematic method for investigating mediation in within-participant designs.
- The framework also allows for the examination of moderation effects within the context of within-participant treatments.
Conclusions:
- The proposed ordinary least squares (OLS) estimation method offers a viable solution for analyzing mediation and moderation in within-participant studies.
- This contributes a much-needed systematic procedure, advancing the quantitative analysis of treatment effects in psychological research.
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