Programme of work 1: Evaluating complex interventions

1. Evaluating complex interventions

Evaluating complexity

Existing methods for impact evaluation are most appropriate when investigating the effectiveness of simple interventions. When development projects make a single change in a given context, it is easier to randomise treatment, control other variables and consequently draw robust inferences about the effect of that intervention. However, many interventions are complex. They involve a combination of several activities and/or work in challenging contexts, which make randomisation difficult for practical or ethical reasons. There may be a long and complex causal chain between the implementation of an intervention and the desired outcomes and impact. From a policymaker, implementer and donor perspective, the implication is that it is very difficult to know the impact of an entire portfolio of activity in a given sector and location.

CEDIL projects

CEDIL is supporting research under this programme of work that will develop new approaches to assessing the effectiveness of these more complex interventions, particularly in challenging contexts, such as fragile and conflict-affected states. For example, researchers from the International Security and Development Center, partnered with the American University in Beirut, will evaluate the long-term impact of a complex agricultural intervention conducted by the Food and Agriculture Organization. Using modern computational methods, the project will combine household survey data with satellite imagery and information on conflict, weather, agricultural conditions and productivity. The research will generate rigorous new insights on the causal pathways through which the intervention produces outcomes.

In another project, a team from the University of North Carolina will evaluate the Provincial and Local Government Support Programme in Nepal. This complex intervention aims to build the capacity of local government to administer new powers granted to them by Nepal’s 2015 constitution, which was designed to transition the country to a federal state. The research project will determine the impact of the intervention by applying an innovative case-control design and using cutting-edge methods to correct for selection bias.

The programme of work on evaluating complex interventions also includes evidence synthesis projects which will use the latest meta-analysis methods to, for example, examine the complex impacts of technology-based health interventions and climate-related aid, and understand the ways in which water, sanitation and hygiene interventions have an impact on gender and social equity.