Number needed to sacrifice: statistical taboo or decision-making tool?

Unlabelled: The percentage that benefit from medical preventive measures is small but all are exposed to the risk of side effects so most of those harmed would never benefit from their use. There is no expression or acronym to describe the ratio of harm to benefit nor discussion of what level of harm is acceptable for what benefit. Here we describe the harm to benefit ratio (HBR) expressed as number harmed (H) for 100 to benefit (B) and calculated for commonly used medical interventions.

A randomized questionnaire-based study on the impact of providing numerical information on colorectal cancer screening.

Objectives: To establish whether the provision of numerical data using pictograms and framed as event rates affects subjects' attitudes to colorectal cancer (CRC) screening.

Design: Randomized questionnaire and telephone study comparing a control group given standard NHS CRC information leaflets with an intervention group given the same leaflet but enhanced with additional numerical and pictorial information.

Setting: District General hospital and two general practices in North East England.