title: Performance of the cancer risk management model lung cancer screening module.
abstract: BACKGROUND
  The National Lung Screening Trial (NLST) demonstrated that low-dose computed tomography (LDCT) screening reduces lung cancer mortality in a high-risk U.S. population. A microsimulation model of LDCT screening was developed to estimate the impact of introducing population-based screening in Canada.
  
  
  METHODS
  LDCT screening was simulated using the lung cancer module of the Cancer Risk Management Model (CRMM-LC), which generates large, representative samples of the Canadian population from which a cohort with characteristics similar to NLST participants was selected. Screening parameters were estimated for stage shift, LDCT sensitivity and specificity, lead time, and survival to fit to NLST incidence and mortality results. The estimation process was a step-wise directed search.
  
  
  RESULTS
  Simulated mortality reduction from LDCT screening was 23% in the CRMM-LC, compared with 20% in the NLST. The difference in the number of lung cancer cases over six years varied by, at most, 2.3% in the screen arm. The difference in cumulative incidence at six years was less than 2% in both screen and control arms. The estimated percentage over-diagnosed was 24.8%, which was 6% higher than NLST results.
  
  
  CONCLUSIONS
  Simulated screening reproduces NLST results. The CRMM-LC can evaluate a variety of population-based screening strategies. Sensitivity analyses are recommended to provide a range of projections to reflect model uncertainty.
authors.affiliation: Health Analysis Division, Statistics Canada, Ottawa, Ontario.
authors.forename: William M
authors.initials: WM
authors.lastname: Flanagan
authors.affiliation: McMaster University.
authors.forename: William K
authors.initials: WK
authors.lastname: Evans
authors.affiliation: Canadian Partnership Against Cancer.
authors.forename: Natalie R
authors.initials: NR
authors.lastname: Fitzgerald
authors.affiliation: McMaster University.
authors.forename: John R
authors.initials: JR
authors.lastname: Goffin
authors.affiliation: University of Toronto.
authors.forename: Anthony B
authors.initials: AB
authors.lastname: Miller
authors.affiliation: University of Ottawa.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Wolfson
mesh_terms: D000368:Aged; D002170:Canada / Q000453:epidemiology; D003198:Computer Simulation; D055088:Early Detection of Cancer / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D011829:Radiation Dosage; D012111:Residence Characteristics; D012307:Risk Factors; D012907:Smoking; D014057:Tomography, X-Ray Computed
keywords: LDCT; NLST; low-dose computed tomography; lung cancer screening; microsimulation; simulation