Fig 1.
Flow diagram of the CNBSS [19].
Values in parentheses indicate the number of individuals in each compartment.
Fig 2.
Diagram of the stages of breast cancer incidence and mortality in BCHAM.
Solid arrows indicate transitions from the healthy state, long-dashed arrows from the undetected state, and short-dashed arrows from the detected state.
Fig 3.
A) Effects of tumor aggressiveness k and maximum tumor diameter dmax on Gompertz growth. B) Effects of treatment effectiveness α and tumor size at detection dde on the hazard rate in a semi-log graph where k is kept fixed at 0.1.
Table 1.
Definitions, values and units of model parameters (see also Table 2).
Citations indicate the source for parameter values, with three parameters estimated from the data as noted.
Table 2.
Study-specific values of BCHAM parameters based on the design of the CNBSS [5, 23].
Fig 4.
The number of simulated (box-plots) versus recorded (red square, CNBSS) breast cancers diagnosed and deaths from breast cancer in mammography arm (MA) and control arm (CA).
Fig 5.
Simulated (box-plots) versus recorded (red square, CNBSS) number of breast cancers diagnosed in mammography arm (MA) and control arm (CA) by study year.
Table 3.
Comparison of simulated versus recorded ages at diagnosis (at cancer death in 25 years) for breast cancer detecting during screening phase (from the beginning of follow-up to the 5th year) in mammography arm versus control arm.
Fig 6.
Survivorship as a function of the treatment effectiveness parameter α.
Fig 7.
Benefit (increase in probability of surviving patients after 25 years of follow-up) and harm (increase in probability of patients diagnosed with cancers that would not have been the cause of death) of mammography screening.
Size of dots indicates age, the size increases with age. Color saturation increases with value of dmax. Markers indicate value of k, triangle (square) corresponds to the smallest (largest) value of k. A) The baseline case, and B) the high risk case with an increase of breast cancer incidence by a factor of 5 in comparison with the baseline case presented.
Fig 8.
Comparison of simulated mammography and control arms after bootstrap analysis.
The aggressiveness class indicates the value of the tumor aggressiveness parameter k (1 represents k < 0.0275, 2 from 0.0275–0.0400, 3 from 0.040–0.0543, 4 from 0.0543–0.0726, 5 from 0.0726–0.104 and 6 values greater than 0.104). The maximum tumor diameter class indicates the parameter dmax, with all values in mm (1 represents dmax < 22.36, 2 from 22.36–43.36, 3 from 43.36–64.16, 4 from 64.16–85.05, 5 from 85.05–106.4 and 6 values greater than 106.4). Ranges are from 500 bootstrap replicates of the simulated data. Panels A) and B) show the difference in the number of patients per thousand diagnosed (top number) and the difference in the number per thousand who would have died first of other causes with ineffective treatment (bottom number, α = 2.5). Colors indicate the significance of the difference in probability of diagnosis in the two arms (red for higher in mammography arm, green for lower). Panels C) and D) show the difference in the number of patients per thousand who died of any cause (top number) and the hazard ratio associated with mammography (bottom number) and colors indicate the significance of the effect of mammography on survival (red for higher hazard in the mammography arm, green for lower).