Evaluability assessments as an approach to supporting healthy weight

Evaluability assessment (EA) is a low-cost pre-evaluation activity that can make the best use of limited evaluation resources by improving both the quality and usefulness of evaluations, and the quality and effectiveness of the programmes being evaluated. We conducted seven EAs as part of an evaluation of Medway Council's Supporting Healthy Weight services. This article describes the processes we went through, outlines some of the lessons learned, and shares the benefits of such an approach. We created logic models using programme information and interviews with the Supporting Healthy Weight team. We examined differences between the intended programme and the actual programme, and identified key issues and changes made during implementation. This allowed us to speculate about whether the programme was likely to reach the target audience and achieve the desired impact. From this we identified key information needs and priority evaluation questions. The EAs allowed Medway's public health team to prioritise which programmes needed to be fully evaluated as well as how, why and when. This enabled more cost-effective targeting of limited evaluation resources. The EAs culminated in recommendations for programme improvement, data improvement and capacity strengthening that will have an impact across the whole suite of healthy weight services.