Prevention Science

, Volume 10, Issue 2, pp 87–99 | Cite as

A General Model for Testing Mediation and Moderation Effects

  • Amanda J. Fairchild
  • David P. MacKinnon


This paper describes methods for testing mediation and moderation effects in a dataset, both together and separately. Investigations of this kind are especially valuable in prevention research to obtain information on the process by which a program achieves its effects and whether the program is effective for subgroups of individuals. A general model that simultaneously estimates mediation and moderation effects is presented, and the utility of combining the effects into a single model is described. Possible effects of interest in the model are explained, as are statistical methods to assess these effects. The methods are further illustrated in a hypothetical prevention program example.


Mediation Indirect effect Moderation Mediated moderation Moderated mediation 


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Copyright information

© Society for Prevention Research 2008

Authors and Affiliations

  1. 1.Department of PsychologyUniversity of South Carolina, Barnwell CollegeColumbiaUSA
  2. 2.Research in Prevention Lab, Department of PsychologyArizona State UniversityTempeUSA

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