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Published on: September 11, 2021
Estimating intervention effects of prevention programs: accounting for noncompliance
Elizabeth A Stuart1, Deborah F Perry, Huynh-Nhu Le
1Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, 624 N Broadway, 8th Floor, Baltimore, MD 21205, USA. estuart@jhsph.edu
Summary
Estimating treatment effects in behavioral interventions is complex due to non-compliance. This paper introduces complier average causal effects (CACE) and instrumental variables (IV) methods for analyzing actual participation in prevention trials.
Area of Science:
- Behavioral Science
- Biostatistics
- Public Health
Background:
- Non-compliance with assigned treatments is prevalent in randomized evaluations of behavioral interventions.
- Both treatment and control groups may exhibit varying levels of adherence or engagement.
- Estimating the effect of assignment versus actual participation is crucial for understanding intervention impact.
Purpose of the Study:
- To introduce complier average causal effects (CACE) and instrumental variables (IV) methods.
- To explain the assumptions and limitations of CACE and IV approaches in prevention science.
- To illustrate the application of CACE and IV methods using case studies from prevention trials.
Main Methods:
- The paper focuses on complier average causal effects (CACE) and instrumental variables (IV) statistical methods.
- These methods are applied to randomized controlled trials (RCTs) of preventive interventions.
- Case studies involve interventions for perinatal depression and aggressive disruptive behavior in children.
Main Results:
- CACE and IV methods allow for the estimation of the causal effect of *actually participating* in an intervention.
- The paper highlights the practical application and interpretation of these methods in real-world prevention research.
- Understanding these methods helps researchers address challenges posed by non-compliance in RCTs.
Conclusions:
- CACE and IV methods are valuable tools for analyzing intervention effects when compliance varies.
- Familiarity with the assumptions and limitations of CACE and IV is essential for rigorous prevention science.
- These methods enhance the ability to draw valid conclusions from randomized trials of behavioral interventions.
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