title: Cost-effectiveness of opportunistic versus organised mammography screening in Switzerland.
abstract: BACKGROUND
  Various centralised mammography screening programmes have shown to reduce breast cancer mortality at reasonable costs. However, mammography screening is not necessarily cost-effective in every situation. Opportunistic screening, the predominant screening modality in several European countries, may under certain circumstances be a cost-effective alternative. In this study, we compared the cost-effectiveness of both screening modalities in Switzerland.
  
  
  METHODS
  Using micro-simulation modelling, we predicted the effects and costs of biennial mammography screening for 50-69 years old women between 1999 and 2020, in the Swiss female population aged 30-70 in 1999. A sensitivity analysis on the test sensitivity of opportunistic screening was performed.
  
  
  RESULTS
  Organised mammography screening with an 80% participation rate yielded a breast cancer mortality reduction of 13%. Twenty years after the start of screening, the predicted annual breast cancer mortality was 25% lower than in a situation without screening. The 3% discounted cost-effectiveness ratio of organised mammography screening was euro11,512 per life year gained. Opportunistic screening with a similar participation rate was comparably effective, but at twice the costs: euro22,671-24,707 per life year gained. This was mainly related to the high costs of opportunistic mammography and frequent use of imaging diagnostics in combination with an opportunistic mammogram.
  
  
  CONCLUSIONS
  Although data on the performance of opportunistic screening are limited, both opportunistic and organised mammography screening seem effective in reducing breast cancer mortality in Switzerland. However, for opportunistic screening to become equally cost-effective as organised screening, costs and use of additional diagnostics should be reduced.
authors.affiliation: Erasmus MC, Department of Public Health, Rotterdam, The Netherlands. r.degelder@erasmusmc.nl
authors.forename: Rianne
authors.initials: R
authors.lastname: de Gelder
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Bulliard
authors.forename: Chris
authors.initials: C
authors.lastname: de Wolf
authors.forename: Jacques
authors.initials: J
authors.lastname: Fracheboud
authors.forename: Gerrit
authors.initials: G
authors.lastname: Draisma
authors.forename: Doris
authors.initials: D
authors.lastname: Schopper
authors.forename: Harry J
authors.initials: HJ
authors.lastname: de Koning
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality; D002138:Calibration; D003198:Computer Simulation; D003362:Cost-Benefit Analysis; D055088:Early Detection of Cancer; D005260:Female; D017048:Health Care Costs; D006801:Humans; D008327:Mammography / Q000191:economics* / Q000379:methods; D008403:Mass Screening / Q000191:economics* / Q000379:methods; D008875:Middle Aged; D017059:Models, Econometric; D019057:Quality-Adjusted Life Years; D012680:Sensitivity and Specificity; D013557:Switzerland