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. 2023 Jul 11;43(6):719–736. doi: 10.1177/0272989X231184175

Table 1.

Unknown Parameters of CRC-AIM Natural History Model

Unknown Parameter Plausible Range Best Parameter Value Selected by Calibration
Adenoma generation
 Baseline log risk, β0 β0~TN[7,5](6.3,0.4) −5.661
 Standard deviation of baseline log-risk, σ0 σ0~TN[1,2](1.1,0.2) 1.270
 Sex effect, β1 β1~TN[0.5,0.1](0.5,0.1) −0.384
 Age effect (ages 20–<50), β2 β2~TN[0.03,0.07](0.045,0.007) 0.039
 Age effect (ages 50–<60), β3 β3~TN[0.01,0.05](0.03,0.01) 0.023
 Age effect (ages 60–<70), β4 β4~TN[0.01,0.05](0.03,0.01) 0.020
 Age effect (ages ≥70), β5 β5~TN[0.02,0.03](0.03,0.03) −0.018
Adenoma growth (time to 10 mm)
 Scale (colon), sc sc~U(10.7,40) 24.364
 Shape (colon), αc αc~U(0.5,4) 1.388
 Scale (rectum), sr sr~U(5,20) 6.734
 Shape (rectrum), αr αr~U(2,5) 3.601
Adenoma growth (Richard’s growth model)
 Shape parameter, p p~TN[0.5,3.2](1.0,0.5) 0.710
Transition from adenoma to cancer
 Size (male, colon), γ1cm γ1cm~U(0.02,0.06) 0.040
 Age at initiation (male, colon), γ2cm γ2cm~U(0.0,0.02) 0.016
 Size (male, rectum), γ1rm γ1rm~U(0.02,0.07) 0.039
 Age at initiation (male, rectum), γ2rm γ2rm~U(0.0,0.02) 0.004
 Size (female, colon), γ1cf γ1cf~U(0.02,0.05) 0.043
 Age at initiation (female, colon), γ2cf γ2cf~U(0.0,0.02) 0.014
 Size (female, rectum), γ1rf γ1rf~U(0.02,0.055) 0.035
 Age at initiation (female, rectum), γ2rf γ2rf~U(0.0,0.02) 0.010
Sojourn time
 Scale (colon), λc λc~U(3.0,5.0) 4.683
 Shape (colon and rectum), k k~U(2.0,5.0) 3.620
 Log-hazard ratio, α α~U(1.0,1.0) −0.018

TN[a,b](μ,σ) represents a truncated normal distribution with mean µ and standard deviation σ over the domain [a,b]. U(a,b) represents a uniform distribution with domain (a,b). CRC-AIM, Colorectal Cancer-Adenoma Incidence and Mortality Model.