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. 2023 Mar 25;23:70. doi: 10.1186/s12874-023-01876-x

Table 2.

Performance indicators of conventional model and Model(1) using Maximum likelihood estimation on grouped data by different α

Scenario Method true value α AB SD CVR
α π60 λ γ β δ α π60 λ γ β δ α π60 λ γ β δ
BREASTa conventional 2 − 0.281 − 0.042 0.011 −0.911 − 0.012 0.046 0.005 0.029 0.097 0.100 0% 0% 96% 0% 95%
Model(1) 2 −0.005 −0.004 0.000 0.002 −0.011 −0.005 0.115 0.043 0.012 0.048 0.199 0.157 93% 93% 93% 95% 93% 94%
conventional 1.5 −0.173 −0.030 − 0.028 −0.627 0.140 0.036 0.006 0.033 0.093 0.092 0% 0% 88% 0% 64%
Model(1) 1.5 −0.001 −0.003 0.000 0.002 −0.007 −0.004 0.099 0.038 0.011 0.046 0.184 0.146 94% 93% 95% 95% 94% 94%
conventional 1.2 −0.075 − 0.016 − 0.029 − 0.314 0.142 0.027 0.006 0.037 0.104 0.093 8% 30% 89% 18% 71%
Model(1) 1.2 0.000 −0.003 0.000 0.002 −0.007 − 0.003 0.090 0.036 0.010 0.045 0.174 0.139 93% 94% 96% 96% 94% 94%
conventional 1 −0.001 0.000 0.000 −0.002 0.000 0.018 0.007 0.040 0.097 0.106 95% 95% 95% 95% 94%
Model(1) 1 −0.001 −0.003 0.000 0.002 −0.009 −0.001 0.084 0.034 0.010 0.044 0.169 0.134 93% 94% 95% 96% 94% 93%
conventional 0.8 0.058 0.017 0.048 0.299 −0.221 0.011 0.008 0.042 0.084 0.106 2% 40% 79% 4% 41%
Model(1) 0.8 −0.001 − 0.002 0.000 0.002 −0.007 −0.002 0.077 0.033 0.009 0.043 0.161 0.129 94% 92% 95% 95% 93% 93%
LUNGb conventional 2 −0.010 − 0.012 − 0.032 − 0.131 0.017 0.004 0.013 0.014 0.061 0.023 22% 85% 35% 45% 86%
Model(1) 2 −0.006 0.002 − 0.009 − 0.001 0.003 0.003 0.206 0.004 0.014 0.015 0.065 0.023 96% 92% 89% 95% 95% 95%
conventional 1.5 −0.004 −0.011 − 0.016 − 0.061 0.011 0.004 0.013 0.014 0.059 0.023 84% 88% 76% 84% 92%
Model(1) 1.5 − 0.004 0.002 − 0.009 − 0.001 0.003 0.003 0.165 0.004 0.013 0.014 0.063 0.023 96% 92% 89% 94% 95% 94%
conventional 1.2 0.000 − 0.010 − 0.007 − 0.022 0.006 0.004 0.013 0.014 0.058 0.023 96% 89% 91% 95% 93%
Model(1) 1.2 0.000 0.002 −0.009 0.000 0.004 0.003 0.149 0.004 0.013 0.014 0.062 0.023 95% 92% 90% 94% 94% 93%
conventional 1 0.002 − 0.009 0.000 0.002 0.002 0.004 0.015 0.015 0.061 0.026 92% 98% 98% 95% 97%
Model(1) 1 0.001 0.002 −0.009 0.000 0.004 0.003 0.132 0.004 0.013 0.014 0.061 0.023 96% 91% 90% 94% 94% 94%
conventional 0.8 0.005 −0.008 0.006 0.028 0.000 0.004 0.013 0.013 0.057 0.022 75% 90% 92% 92% 94%
Model(1) 0.8 −0.002 0.002 −0.009 0.000 0.003 0.003 0.121 0.004 0.013 0.014 0.060 0.022 95% 91% 90% 94% 94% 93%

Absolute Bias (AB) = Mean(estimates - true value); Standard Deviation (SD) = standard deviation over the set of 1000 estimates; Coverage (CVR) = the proportion of the time that the estimated 95% confidence intervals contained the true value. Estimated over 1000 simulation runs; Sample size 10,000; follow-up 15 years

aTrue values: π60 = 0.7, λ =0.1, γ =1.1, β = − 0.15 and δ = 0. bTrue values: π60 = 0.1, λ =0.9, γ =0.8, β = − 0.75 and δ = − 0.3