[Preffi 2.0: a Dutch instrument to analyse the effectiveness of health promotion interventions].

Preffi is a set of guidelines with items relevant to the effectiveness of health promotion projects, reflecting scientific and practical knowledge. Preffi is used to assess quality at various stages of an intervention, either to critically evaluate one's own project or to comment on projects proposed by others. This article describes the Preffi model, its scoring method and the systematic, seven-step development process that led to its second version: Preffi 2.0. The draft version of Preffi 2.0 was tested for usefulness among 35 experienced Health Promotion specialists. They gave the instrument an average overall score of 7.7 on a scale of 10. The large majority of them evaluated it as valuable, complete, clear, well-organised and innovative. Users have commented that applying Preffi to a project yields a balanced and useful assessment, as well as a clear overview of points in the project that could be improved.