The number of women who would need to be screened regularly by mammography to prevent one death from breast cancer

University of Oxford, UK.
Journal of Medical Screening (Impact Factor: 3.1). 12/2011; 18(4):210-2. DOI: 10.1258/jms.2011.011134
Source: PubMed


The number of women who would need to be screened regularly by mammography to prevent one death from breast cancer depends strongly on several factors, including the age at which regular screening starts, the period over which it continues, and the duration of follow-up after screening. Furthermore, more women would need to be INVITED for screening than would need to be SCREENED to prevent one death, since not all women invited attend for screening or are screened regularly. Failure to consider these important factors accounts for many of the major discrepancies between different published estimates. The randomised evidence indicates that, in high income countries, around one breast cancer death would be prevented in the long term for every 400 women aged 50-70 years regularly screened over a ten-year period.

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Available from: Rosalind Given Wilson
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    • "The group concluded that for biennial screening for 20 years starting at age 50 in a typical European country, and with follow-up to age 79, a 38–48% reduction in breast cancer mortality and overdiagnosis of 6.5% of all breast cancer would be expected in screened women (Paci and EUROSCREEN Working Group, 2012). Differences in estimates of benefits and harms of mammography screening may be due to differences in delivered interventions, data sources used, the choice of denominators, and length of follow-up (Beral et al, 2011; Paci and EUROSCREEN Working Group, 2012). "
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