Fortney J, Booth B, Zhang M, Humphrey J, Wiseman E; Association for Health Services Research. Meeting.
Abstr Book Assoc Health Serv Res Meet. 1997; 14: 179.
Centers for Mental Healthcare Research, Department of Psychiatry, University of Arkansas for Medical Sciences, Little Rock 72205, USA.
RESEARCH OBJECTIVES: Because of the treatment context, randomized controlled trials are not appropriate for Alcholics Anonymous (AA) treatment effectiveness and outcomes research. On the other hand, observational studies of AA participation are subject to selection bias whenever the self-selection process results in important differences in unobserved casemix dimensions between treatment groups. The purpose of this research was to control for self-selection bias in the evaluation of AA as aftercare treatment. STUDY DESIGN: The sample included 118 veterans discharged from inpatient alcohol treatment, 85% of whom were followed-up at three months. Drinking outcomes were measured by self reported abstinence in the third month after discharge. The aftercare treatment effect of AA was estimated using standard logistic regression analysis and Instrumental Variables analysis. The instruments included variables representing accessibility to AA meetings. A Hausman exogeniety test was used to determine whether the standard logistic regression were subject to self-selection bias. PRINCIPAL FINDINGS: Estimates from the standard logistic regression yielded a positive (OR=3.7) and significant (p=0.018) treatment effect for AA attendance. However, the Instrumental Variables analysis yielded a smaller (OR=1.7) and insignificant treatment effect estimate (p=0.782). The Hausman exogeniety test indicated that the treatment effect estimate from the standard logistic regression was subject to significant self-selection bias (c2=83.9, p<0.01). CONCLUSIONS: The AA aftercare treatment effect observed in this sample was due to differences in unobserved casemix factors between the treatment groups (i.e., selection bias). AA meeting attendance had no significant impact on drinking outcomes, controlling for selection bias. RELEVANCE: Results suggest that previous AA aftercare research may have been subject to self-selection bias which potentially overestimated the actual treatment effect of AA.
Publication Types:
Keywords:
- Aftercare
- Alcoholics Anonymous
- Ambulatory Care
- Hospitalization
- Long-Term Care
- Patient Discharge
- Research Design
- Selection Bias
- Treatment Outcome
- Veterans
- methods
- prevention & control
- therapy
- hsrmtgs
Other ID:
UI: 102233671
From Meeting Abstracts