Authors: Siobhan Campbell, Gemma Harper
Published by HM Treasury, Dept of Energy and Climate Change, Dept of Environment, Food and Rural Affairs, December 2012
Quality in policy impact evaluation (QPIE) is a supplement to the Magenta Book  (see below) and provides a guide to the quality of impact evaluation designs. It has been developed to aid policy makers and analysts understand and make choices about the main impact evaluation designs by understanding their pros and cons and how well each design can allow for any measured change to be attributed to the policy intervention being investigated.
Chapter 1 Introduction
Chapter 2 Quality in policy impact evaluation
Chapter 3 Strong research designs in the measurement of attribution
Chapter 4 Weaker/riskier research designs in the measurement of attribution
Annex A Acknowledgements
Annex B References
The Magenta Book
27 April 2011
The Magenta Book is HM Treasury guidance on evaluation for Central Government, but will also be useful for all policy makers, including in local government, charities and the voluntary sectors. It sets out the key issues to consider when designing and managing evaluations, and the presentation and interpretation of evaluation results. It describes why thinking about evaluation before and during the policy design phase can help to improve the quality of evaluation results without needing to hinder the policy process.
The book is divided into two parts.
Part A is designed for policy makers. It sets out what evaluation is, and what the benefits of good evaluation are. It explains in simple terms the requirements for good evaluation, and some straightforward steps that policy makers can take to make a good evaluation of their intervention more feasible.
Part B is more technical, and is aimed at analysts and interested policy makers. It discusses in more detail the key steps to follow when planning and undertaking an evaluation and how to answer evaluation research questions using different evaluation research designs. It also discusses approaches to the interpretation and assimilation of evaluation evidence.
The Magenta Book will be supported by a wide range of forthcoming supplementary guidance containing more detailed guidance on particular issues, such as statistical analysis and sampling.
The Magenta Book is also available for download in PDF format:
- Magenta Book (PDF 1.2MB) 
- Part A of the Magenta Book (PDF 161KB) 
- Part B of the Magenta Book (PDF 785KB)