Table 3.

HRs for effect of exposures in current and former smokers estimated in the training set and their predictive value in the test set

HR (95% CI)PP for improvement in AUCtdNRI
ChangeP
CovariateCurrentFormerCurrentFormerCurrentFormerCurrentFormerCurrentFormer
Sex: female 1, male 0.1.35 (1.16–1.57)1.2 (0.91–1.59)0.0001260.1940.885−0.346−0.3210.990.937
BMI0.963 (0.946–0.98)0.96 (0.929–0.992)3.7 × 10−50.0148−0.0709−0.2060.6870.82
Education level (greater than high school)0.944 (0.751–1.19)0.436 (0.275–0.691)0.620.0004180.2430.235−0.07630.010.637
Hay fever0.593 (0.335–1.05)0.901 (0.494–1.64)0.07280.734++0.2330.120.1390.366
Asthma0.85 (0.546–1.32)1.58 (0.961–2.6)0.4740.071++0.0437−0.01270.3460.504
Family history of cancer1.27 (0.758–2.11)1.23 (0.694–2.16)0.3680.484++−0.217−0.2350.90.845
Chr15q251.13 (1.01–1.27)1.14 (0.933–1.38)0.03360.2020.7260.3090.4060.3810.23
Chr5p150.954 (0.845–1.08)1.06 (0.865–1.3)0.4420.5720.7650.8851.3−0.4950.0670.808
Occupational exposures
 Silica0.893 (0.602–1.33)0.851 (0.349–2.07)0.5740.722++−0.0252−0.09070.6840.945
 PAH0.988 (0.808–1.21)0.869 (0.586–1.29)0.9060.4850.6710.0177−0.1940.4280.871
 Metal0.961 (0.794–1.16)1.23 (0.866–1.74)0.680.2490.308−0.3850.2810.9960.06
 Asbestos0.943 (0.775–1.15)1.05 (0.738–1.49)0.5580.7840.603−0.240.2960.9860.029

NOTE: Exposure effects are conditional on lifetime exposure to cigarette smoke. P value for improvement in AUC and tdNRI compares predictive performance of model with and without covariate (tdNRI P values were calculated by permutation). AUC P values are not shown for covariates whose inclusion decreased the AUC (denoted by −) and there were fewer than 5 exposed cases (denoted by +).