title: Swiss Medical Board Mammography screening predictions for Switzerland: importance of time-periods.
abstract: OBJECTIVE
  In 2013, the Swiss Medical Board (SMB) concluded that for three breast cancer screens over 13 years in Switzerland, cost-effectiveness was negative, with no additional benefits in quality-adjusted life-years gained. We compared these suggested predicted effects with other estimates.
  
  
  METHODS
  We used an extensively validated model on the natural history of breast cancer in Switzerland, comparing a 13-year time frame, a life-time perspective, and a continuous screening programme, per 10,000 Swiss women. Both approaches used the Swedish randomized controlled trials for the theoretical effect.
  
  
  RESULTS
  Over 13 years, both approaches yield comparable life-years gained (56 versus 67), but in expectation in 10,000 women's lifetimes 444 life-years are gained, and in a continuous screening programme (instead of three screens) 839 years. The SMB estimate of 56 life-years gained is counterweighted by 57 negative quality of life adjusted years, primarily resulting from a 5% annual loss for 10% of women, being false-positive results. International literature is consistent with more than four times lower losses on false-positives. The estimate of overdiagnosed cases in the 13-year time frame was four times higher than in the long-term perspective.
  
  
  CONCLUSIONS
  By restricting life-years gained to a 13-year time frame the SMB prediction on benefits of mammography screening is unrealistically low. Predicting long-term harms and benefits, specifically tailored to observations, regarding the clinical situation before screening commences, and possible data during a screening programme, are crucial for women, professionals, and policymakers.
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands h.dekoning@erasmusmc.nl.
authors.forename: H J
authors.initials: HJ
authors.lastname: de Koning
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: E A M
authors.initials: EA
authors.lastname: Heijnsdijk
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000191:economics; D003362:Cost-Benefit Analysis / Q000379:methods; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D017048:Health Care Costs; D006801:Humans; D008327:Mammography / Q000191:economics* / Q000379:methods / Q000706:statistics & numerical data; D008403:Mass Screening / Q000191:economics* / Q000379:methods / Q000706:statistics & numerical data; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D016032:Randomized Controlled Trials as Topic; D013557:Switzerland
keywords: HTA; Mammography; bias; follow up; modelling