Improving The Quality | Of The Written Information Sent To Women About Breast Screening- Evidence-based Criteria For The Content Of Letters And Leaflets -nhsbsp Publication-

The most radical change is the insistence on using absolute risk reductions rather than relative risk reductions. For example, stating that screening reduces the risk of dying from breast cancer from 0.3% to 0.2% (an absolute reduction of 0.1%) is very different from stating it reduces mortality by 33% (relative reduction). The evidence-based criteria mandate absolute numbers, accompanied by clear denominators (e.g., "out of 1,000 women screened"). This prevents the cognitive bias that exaggerates perceived benefit.

State clearly how many lives are saved per 1,000 women screened. The most radical change is the insistence on

Historically, invitation letters for breast screening were designed with a single, implicit goal: maximise uptake. Consequently, the language used was often directive and emotive, emphasising the life-saving potential of screening while omitting or downplaying significant harms such as false positives, overdiagnosis (detecting cancers that would never cause symptoms), and unnecessary treatment. This approach created a "gratitude effect," where women felt obliged to attend without the tools to weigh the trade-offs. The NHSBSP publication directly confronted this ethical failing, asserting that high-quality written information is a clinical and moral necessity. The criteria established in the document are not arbitrary suggestions but are derived from systematic reviews of what women actually need to know to make a decision aligned with their personal values. This prevents the cognitive bias that exaggerates perceived

NHSBSP No. 55 introduced strict rules around the phrase "lives saved." The evidence showed that women vastly overestimated the benefit. The criteria required that any mention of mortality reduction must be accompanied by a numeric table (e.g., "For every 200 women screened regularly for 10 years, 1 death from breast cancer is prevented"). Consequently, the language used was often directive and