Bringing rigor to evaluations of large-scale programs to improve infant and young child feeding and nutrition: the evaluation designs for the Alive & Thrive initiative.

BACKGROUND: The evidence base on the impact of large-scale infant and young child feeding (IYCF) and nutrition programs is limited, partly due to the challenges of rigorously evaluating complex programs including multiple interventions.
OBJECTIVES: To describe the process used to design Alive & Thrive's impact evaluations in the three target countries and discuss the feasibility of developing contextually relevant designs adapted to the country-specific programmatic context.
METHODS: The evaluation designs for Alive & Thrive needed to address several challenges. These included the selection of intervention components to evaluate rigorously; the identification of appropriate comparison groups in the context of rapidly scaling-up programs; the choice of impact indicators; addressing measurement challenges related to evaluating the impact of interventions targeted during the first 2 years of life on stunting; and developing methods and tools to assess implementation, utilization, and program impact pathways within evolving program portfolios.
RESULTS: In Bangladesh and Vietnam, cluster-randomized probability designs are used for the impact evaluations; in Ethiopia, the impact evaluation uses an adequacy design. In all three countries, repeated cross-sectional surveys, 4 years apart, are used to measure impact, and appropriate age groups are sampled separately to capture change in the main impact indicators. In addition, theory-driven process evaluations are used to study factors that facilitate or prevent achievement of impact and scale.
CONCLUSIONS: We conclude that robust impact and process evaluations of complex, large-scale nutrition programs are feasible, but that early implementer-evaluator engagement and shared vision and motivation to establishing meaningful evaluations are essential.