Misunderstanding data: Can researchers simplify longitudinal data for policymakers without it leading to errors?

Following the comments made on evidence-based policymaking by the Rt Hon David Willetts MP, Leon Feinstein provides further background on the longitudinal data discussed and defends the findings against some key misunderstandings of the data. For those trying to enhance the use of evidence, an important question is always how to simplify without introducing error and understating uncertainty.