Abstract
This study evaluated the effectiveness of the three approaches for treating dual disorder clients who were homeless at intake: integrated assertive community treatment (IACT), assertive community treatment only (ACTO), and standard care (SC). Multilevel Random Coefficient Modeling (MRCM) was used to analyze longitudinal effects and to identify mediators of significant treatment effects. The outcome variables were consumer satisfaction, stable housing, psychiatric symptoms, and substance abuse. The eight mediators were service utilization variables: program contacts, phone contacts, substance abuse contacts, assistance with activities of daily living, transportation assistance, help finding permanent housing, help with emotional problems, and medication assistance. The 191 eligible participants were randomly assigned to one of the three conditions and followed for a period of 30 months. Both ACTO and IACT produced better outcomes than SC on consumer satisfaction and stable housing. There were no differences on any of the outcome variables between ACTO versus IACT when comparing main effects. However, there were several treatment by time interactions. In addition, there were many mediation effects.
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Notes
We acknowledge that spurious interactions are unlikely (Evans 1985). Therefore, we note the exact P-values and allow the reader to determine the importance of the effects when interactions are significant at the P < .1 level. We retain the convention of P < .05 when reporting the main effects.
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Acknowledgments
The authors thank the study participants for their cooperation in this study; we hope that their lives have improved as a result of their participation. We also appreciate the cooperation of the many agencies that provided treatment to the study participants, particularly Community Alternatives, Places for People, and Peter and Paul Community Services. The following individuals were critical to the execution of the project: Ruth Smith, Mary Maguire, Bill Tourville, Joris Miller, Gretchen Gerteis, Gail Saulnier, Kecia Smith, Dorothy Gano, Jean Mayo, and Melinda Bowen. Dr. Robert E. Drake and his colleagues provided consultation throughout the project. Financial support was provided by the National Institute of Mental Health (MH 57154) and the University of Missouri-St. Louis. However, the views expressed in this paper are the sole responsibility of the authors.
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Fletcher, T.D., Cunningham, J.L., Calsyn, R.J. et al. Evaluation of Treatment Programs for Dual Disorder Individuals: Modeling Longitudinal and Mediation Effects. Adm Policy Ment Health 35, 319–336 (2008). https://doi.org/10.1007/s10488-008-0170-2
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DOI: https://doi.org/10.1007/s10488-008-0170-2