Using natural experiments to evaluate population health interventions: guidance for producers and users of evidence

The aim of this guidance is to help producers, users, funders and publishers of evidence understand how and when 'natural experiments' can be used to good effect. While there is growing interest in using natural experiments to evaluate large-scale interventions to improve population health, the relevant methodological literature is dispersed across disciplines and there is a lack of general guidance either on the range of approaches available, or on the circumstances in which they are likely to be useful. We aim to fill this gap