AIDS and Behavior

, Volume 11, Issue 3, pp 365–383 | Cite as

Mediational Analysis in HIV/AIDS Research: Estimating Multivariate Path Analytic Models in a Structural Equation Modeling Framework

  • Angela BryanEmail author
  • Sarah J. Schmiege
  • Michelle R. Broaddus
Review Paper


Mediational analyses have been recognized as useful in answering two broad questions that arise in HIV/AIDS research, those of theoretical model testing and of the effectiveness of multicomponent interventions. This article serves as a primer for those wishing to use mediation techniques in their own research, with a specific focus on mediation applied in the context of path analysis within a structural equation modeling (SEM) framework. Mediational analyses and the SEM framework are reviewed at a general level, followed by a discussion of the techniques as applied to complex research designs, such as models with multiple mediators, multilevel or longitudinal data, categorical outcomes, and problematic data (e.g., missing data, nonnormally distributed variables). Issues of statistical power and of testing the significance of the mediated effect are also discussed. Concrete examples that include computer syntax and output are provided to demonstrate the application of these techniques to testing a theoretical model and to the evaluation of a multicomponent intervention.


Mediation Path analysis Structural equation modeling (SEM) Multicomponent interventions 



The authors would like to thank Dr. David Kenny for serving as a reviewer on this paper. His contributions were invaluable. Preparation of this paper was supported by grants from the National Institute on Alcoholism and Alcohol Abuse (AA013844-01) and the National Institute on Drug Abuse (DA019139-01) awarded to the first author.


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Angela Bryan
    • 1
    Email author
  • Sarah J. Schmiege
    • 1
  • Michelle R. Broaddus
    • 1
  1. 1.Department of PsychologyUniversity of ColoradoBoulderUSA

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