The financial implications of investigating false-positive and true-positive mammograms in a national breast cancer screening program

Objectives To determine the total annual screening and further-investigation costs of investigating false-positive and true-positive mammograms in the Australian population breast-screening program. Methods This economic analysis used aggregate-level retrospective cohort data of women screened at a breast-screening clinic. Counts and frequencies of each diagnostic workup-sequence recorded were scaled up to national figures and costed by estimating per-patient costs of procedures using screening clinic cost data. Main outcomes and measures estimated were percentage share of total annual screening and further-investigation costs for the Australian population breast-screening program of investigating false-positive and true-positive mammograms. Secondary outcomes determined were average costs of investigating each false-positive and true-positive mammogram. Sensitivity analyses involved recalculating results excluding subgroups of patients below and above the screening age range of 50–74 years. Results Of 8235 patients, the median age was 60.35 years with interquartile range of 54.17–67.17 years. A total of 15.4% (ranging from 13.4 to 15.4% under different scenarios) of total annual screening and further-investigation costs were from investigating false-positive mammograms. This exceeded the share of costs from investigating true-positives (13%). Conclusions We have developed a transparent and non-onerous approach for estimating the costs of false-positive and true-positive mammograms associated with the national breast-screening program. While determining an optimal balance between false-positives and true-positive rates must rely primarily on health outcomes, costs are an important consideration. We recommend that future research adopts and refines similar approaches to facilitate better monitoring of these costs, benchmark against estimates from other screening programs, and support optimal policy development.