A cost-benefit analysis of the Swedish model for screening for neoplasma malignum mammae revealed scientific shortcomings in the basis for decision. It was not possible to determine whether the screening model involved a net loss or a net profit for the individual woman. Since false confidence seems to increase the mortality in breast cancer a new dimension was introduced, a sensitivity index as an expression of revealed fractions of the incidence in the participant population. This sensitivity index estimated some two thirds of the malignant neoplasms which are normally diagnosed in a two year period.