Skip to main content

Table 3 Starting ranges used in first round of model calibration – ranges were narrowed with successive rounds of calibration to achieve improved fit to the outcomes reported in the intensive follow-up arm of the Pietra trial[52]

From: A simulation model of colorectal cancer surveillance and recurrence

Parameter Definition Starting range (inclusive) Final calibrated parameter value
r d Rate per 3-month cycle at which recurrences transition from undetectable to detectable 0.05 - 0.12 0.092
x ds Baseline (Di = 0) presymptomatic window 1 week – 9 months 17 weeks
x du Baseline (Di = 0) window of resectability 1 week – 9 months 6 weeks
r s Increment in presymptomatic window for each additional unit of Di (expressed as a rate per 3-month cycle) −0.025 - 0.15 0.07
r u Increment in window of resectability for each additional unit of Di (expressed as a rate per 3-month cycle) 0 - 0.15 0.11
σ ds Standard deviation of normally-distributed error term for presymptomatic window 1 week – 6 months 11 weeks
m Background five-year cumulative probability of mortality from non-CRC causes 1% - 20% 1.6%a
  1. aBy comparison, five year cumulative probability of death from any cause in the Italian population for a group with the age and gender makeup of the calibration group has been estimated at 6.1% for 1990 [51].