Theory of disruption: A method for understanding context in social policy evaluations with a worked example based on the COVID-19 pandemic

The context in which social interventions are piloted and evaluated is critical to success, and there is room for further theoretical and empirical work. Limited knowledge exists about ‘creating the conditions’ for interventions to succeed and about dealing with disruptive changes in context. This article presents a ‘theory of disruption’, to go alongside theories of change and harm. After discussing the challenge of context, and gaps in research, we present a worked example that uses a reoriented logic model to describe the impact of unexpected changes in the wider context of a recent evaluation. This considers the COVID-19 pandemic as a disruptive force on an ongoing school-based intervention. The pandemic is considered an intervention in itself, and the disruptive effects it created are mapped and discussed. The article concludes by considering other uses of the method, including to theorise and measure the effects of a wide range of changes in context.