title: Breast cancer mortality in mammographic screening in Europe: a review of incidence-based mortality studies.
abstract: OBJECTIVE
  To estimate the impact of service mammography screening on breast cancer mortality using European incidence-based mortality (IBM) studies (or refined mortality studies). IBM studies include only breast cancer deaths occurring in women with breast cancer diagnosed after their first invitation to screening.
  
  
  METHODS
  We conducted a literature review and identified 20 publications based on IBM studies. They were classified according to the method used for estimating the expected breast cancer mortality in the absence of screening: (1) women not yet invited; (2) historical data from the same region as well as from historical and current data from a region without screening; and (3) historical comparison group combined with data for non-participants.
  
  
  RESULTS
  The estimated effect of mammography screening on breast cancer mortality varied across studies. The relative risks were 0.76-0.81 in group 1; 0.75-0.90 in group 2; and 0.52-0.89 in group 3. Study databases overlapped in both Swedish and Finnish studies, adjustment for lead time was not optimal in all studies, and some studies had other methodological limitations. There was less variability in the relative risks after allowing for the methodological shortcomings.
  
  
  CONCLUSIONS
  Based on evidence from the most methodologically sound IBM studies, the most likely impact of European service mammography screening programmes was a breast cancer mortality reduction of 26% (95% confidence interval 13-36%) among women invited for screening and followed up for 6-11 years.
authors.affiliation: Department of Public Health, Post Doc, Centre for Epidemiology and Screening, University of Copenhagen,Copenhagen, Denmark. sissenj@sund.ku.dk
authors.forename: Sisse
authors.initials: S
authors.lastname: Njor
authors.forename: Lennarth
authors.initials: L
authors.lastname: Nyström
authors.forename: Sue
authors.initials: S
authors.lastname: Moss
authors.forename: Eugenio
authors.initials: E
authors.lastname: Paci
authors.forename: Mireille
authors.initials: M
authors.lastname: Broeders
authors.forename: Nereo
authors.initials: N
authors.lastname: Segnan
authors.forename: Elsebeth
authors.initials: E
authors.lastname: Lynge
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis* / Q000401:mortality*; D055088:Early Detection of Cancer / Q000009:adverse effects / Q000706:statistics & numerical data; D005060:Europe; D005260:Female; D006801:Humans; D015994:Incidence; D008327:Mammography; D008403:Mass Screening / Q000009:adverse effects / Q000706:statistics & numerical data