by Sebastian Lemire & Allan Porowski
Evidence reviews have become a key tool for evidence-based policy, helping policymakers make informed decisions about which interventions to implement. Traditionally, these reviews have focused on the outcomes of entire interventions. However, the growing interest in the specific elements that drive intervention effect has over the past ten years led to a focus on core components—the key features that contribute to an intervention’s effectiveness. Core components refer to the essential features of an intervention—such as activities, services, or practices—that available evidence shows are effective in driving outcomes. Identifying these core components can help create more effective interventions by highlighting the features that contribute most to desired outcomes. Identifying with greater precision what works, in which contexts, and for which populations can help policymakers assess which existing policies and interventions are (or are not) likely to be effective and better understand why policies or interventions that share similar characteristics may achieve different results.
In our PSJ research note, we describe four evidence synthesis approaches—distillation and matching model, meta-regression, framework synthesis, and qualitative comparative analysis—to identify these core components. Each approach offers unique advantages depending on the available data and intervention context. Understanding the various approaches, along with their respective advantages and limitations, can help researchers select the most appropriate analysis method based on the purpose of their evidence review, the intended audience, and how the findings will be applied.
To further enhance the use of core components analysis, we call for advancements in improving reporting conventions, using multi-phased designs, and expanding applications of core component analysis. Providing more detailed reporting of the intervention characteristics, setting, participants, implementation, and costs in primary studies provides for a stronger foundation for core components analysis. To enhance core components analyses even further, a multi-phase approach can be used. In the first phase, researchers analyze evidence in a specific field, and in the second phase, they collaborate with practitioners to design field trials based on the findings to evaluate the effectiveness of core components Finally, applying core components analysis across a broader range of interventions, practices, and policies, with more diverse populations, and in a variety of settings can help policymakers understand how evidence-based interventions and policies should be designed to ensure that they promote positive outcomes in diverse contexts.
You can read the original article in Policy Studies Journal at
Lemire, Sebastian, Laura R. Peck, Allan Porowski and Allison Dymnicki. 2025. “ Unpacking Core Components For Policy Design: A Comparison of Synthesis Approaches.” Policy Studies Journal 53(1): 171–184. https://doi.org/10.1111/psj.12567.
About the Authors
Sebastian Lemire is a Senior Scientist at Abt Global. His research focuses on systematic evidence reviews, alternative approaches to impact evaluation, and evaluation capacity building. He currently serves on the executive board of the American Evaluation Association and on the editorial advisory boards of Evaluation and the American Journal of Evaluation.
Allan Porowski is a Principal Associate at Abt Global. He is a leading expert in the design, execution and analysis of randomized controlled trials, quasi-experimental studies and national cross-site evaluations of education, health, and other social interventions.
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