Two view mammography at incident screens: cost effectiveness analysis of policy options.

OBJECTIVE To determine the cost effectiveness of two view mammography at incident screens. DESIGN Incremental cost effectiveness analyses recognising differences in current reading policy, based on effectiveness data from an observational study. SETTING Breast screening programmes in England and Wales. MAIN OUTCOME MEASURES Health service costs, cancers detected, incremental cost effectiveness ratios per cancer detected, whole time equivalent staff. RESULTS For programmes currently using one view with some form of double reading, the incremental cost effectiveness ratio of two view mammography at incident screens ranged between 6589 pounds and 6716 pounds, depending on the reading policy. For programmes currently using one view with single reading, two policy options were found to be more efficient than two view single reading: one view with double reading (arbitration; incremental cost effectiveness ratio of 210 pounds) and two view double reading (arbitration). If programmes using one view with single reading changed to double reading (arbitration) and then subsequently to two views double reading (arbitration), additional cancers could be detected with an incremental cost effectiveness ratio of 7983. The implementation cost of two view mammography at incident screens in programmes in England and Wales would be 2.9 million pounds and would require 13.4 whole time equivalent radiologists. CONCLUSIONS The cost effectiveness of two view mammography at incident screens depends on the film reading policy. A policy of two view mammography at incident screens in England and Wales would be efficient only if programmes using single reading moved to double reading. Given limited resources, priority should be given to introducing double reading in the subset of programmes currently using single reading as this requires fewer additional radiologists and is more cost effective.