The Use of Contribution Analysis in Evaluating Health Interventions: A Scoping Review.

Contribution Analysis (CA) is a promising theory-based evaluation approach for complex interventions, yet its application in health interventions remains largely unexplored. To bridge this gap, we conducted a scoping review to examine the extent of such applications and the methodologies, strengths, and limitations of this approach in health programming. Our comprehensive search strategy was developed and used in 15 databases to identify peer-reviewed articles from 1999 to 2023 that focused on using CA to evaluate health interventions. We then implemented rigorous double- and triple-screening processes for abstracts and full-text papers, respectively. Data were extracted and narratively summarized. Our review found seven relevant studies, which showed that CA has been employed in health promotion programs, health policies, and targeted health issues such as nutrition, cardiovascular disease, substance misuse, and suicide prevention. The studies identified strengths of using CA, including its flexible impact evaluation approach, capacity to inform decision-making, and potential to enhance understanding of health programs and policies. However, challenges such as how to determine suitable evidence levels and how to best manage resource intensity were also identified. The limited number of studies indicates that CA is still a novel approach, whereas the variation in the reporting of the studies suggests that this approach could benefit from more standardized methods and detailed stakeholder engagement strategies.