Evaluation of a Risk-Stratified National Breast Screening Programme in the United Kingdom: An updated cost-effectiveness analysis

Abstract
Study objective: To update a published early economic evaluation of exemplar risk-stratified national breast screening programmes (stratified-NBSP).

Method: An existing validated decision-analytic model, using discrete event simulation (the ‘Gray-model’), was used to structure the pathways for 3 stratified-NBSP (risk-1; risk-2; risk-3) compared with the current NBSP in the United Kingdom (UK-NBSP), biannual screening, and no screening. The updated model is called MANC-RISK-SCREEN and assumes a life-time horizon, the UK health service perspective to identify costs (using £; 2022) and measures health consequences using life-years and Quality Adjusted Life Years (QALYs). The original data sources used for the Gray-model were assessed for current relevance and updated where feasible. Updated data sources included: cancer and all-cause mortality; breast cancer incidence; breast cancer risk data; tumour staging; recall rate; mammographic sensitivity by breast density group; costs; and utilities. Model parameter uncertainty was assessed using Probabilistic Sensitivity Analysis (PSA) and one-way sensitivity analysis.

Results: The base case analysis, supported by PSA, suggested that there was always a risk-stratified approach to breast cancer screening that was superior to universal screening. In the base case analysis, a strategy of dividing women into three equal groups based on risk was the most cost-effective. In the PSA, a strategy based on that used in the BC-PREDICT study was the most cost-effective. There was uncertainty in whether the addition of reduced screening for women at lower risk was cost-effective.

Conclusion: The results of this study suggest that risk-stratified approaches to breast cancer screening are more cost-effective than both 3-yearly and 2-yearly universal screening.