When newspapers and scientists want to create the maximum impact for their (usually modest) findings in the field of prevention of heart disease or cancer, they publish the “relative risk” statistics, rather than “absolute risk” statistics.

To explain the two terms and their significance, let me give an example: If the chance of a thing happening is reduced from two per thousand to one per thousand, that is a “relative risk” reduction of 50%, which sounds a lot. But in reality, the “absolute risk” has gone down from 0.2% to 0.1%, or to put that another way, your chance of surviving has been increased from 99.98% to 99.99% which is really very small and nothing like as headline grabbing.

– Barry Groves, PhD