Evaluating policy and service interventions: framework to guide selection and interpretation of study end points

Richard J Lilford, Peter J Chilton, Karla Hemming, Alan J Girling, Celia A Taylor, Paul Barach

The effect of many cost effective policy and service interventions cannot be detected at the level of the patient. This new framework could help improve the design (especially choice of primary end point) and interpretation of evaluative studies.