Table 3.
Intraclass correlation coefficients (ICCs) between the two measurements, 5 years apart, in cigarette smokers and never tobacco users
| Never tobacco users | Cigarette smokers | ||||
|---|---|---|---|---|---|
| Biomarker class | Biomarker | ICC (95% Confidence Interval) |
p value | ICC (95% Confidence Interval) |
p value |
| Nicotine metabolites | COTT | 0.64 (0.45,0.77) | 0.0001 | 0.58 (0.27,0.78) | 0.0001 |
| HCTT | 0.51 (0.29,0.68) | 0.0001 | 0.44 (0.09,0.7) | 0.007 | |
| COXT | NA | 0.45 (0.11,0.7) | 0.006 | ||
| NCTT | NA | 0.51 (0.18,0.74) | 0.002 | ||
| NICT | NA | 0.41 (0.06,0.68) | 0.012 | ||
| NOXT | NA | 0.48 (0.14,0.72) | 0.004 | ||
| NNCT | NA | 0.5 (0.17,0.73) | 0.002 | ||
| Other tobacco alkaloids | ANBT | NA | 0.57 (0.26,0.77) | 0.001 | |
| ANTT | NA | 0.61 (0.31,0.8) | 0.0001 | ||
| Tobacco specific nitrosamines (TSNAs) | NABT | NA | 0.63 (0.34,0.81) | 0.0001 | |
| NATT | NA | 0.64 (0.36,0.81) | 0.0001 | ||
| NNAL | NA | 0.62 (0.34,0.81) | 0.0001 | ||
| NNNT | NA | 0.49 (0.14,0.73) | 0.004 | ||
| Metabolites of polycyclic aromatic hydrocarbons (PAHs) | 1-nap | 0.08 (−0.18,0.32) | 0.283 | 0.51 (0.18,0.74) | 0.002 |
| 2-nap | 0.18 (−0.08,0.42) | 0.087 | 0.43 (0.08,0.69) | 0.009 | |
| 1-phe | 0.31 (0.06,0.53) | 0.003 | 0.09 (−0.28,0.44) | 0.315 | |
| ∑2,3phe | 0.37 (0.13,0.57) | 0.001 | 0.34 (−0.03,0.63) | 0.034 | |
| 2-flu | 0.36 (0.12,0.57) | 0.002 | 0.31 (−0.06,0.61) | 0.049 | |
| 3-flu | 0.44 (0.21,0.62) | 0.0001 | 0.46 (0.12,0.71) | 0.005 | |
| 1-pyr | 0.34 (0.10,0.55) | 0.003 | 0.37 (0.01,0.65) | 0.021 | |
| Metabolites of volatile organic compounds (VOCs) | 2MHA | 0.14 (−0.12,0.38) | 0.15 | 0.48 (0.15,0.72) | 0.004 |
| 34MH | 0.08 (−0.18,0.33) | 0.28 | 0.34 (−0.03,0.63) | 0.034 | |
| AAMA | 0.19 (−0.07,0.43) | 0.073 | 0.27 (−0.11,0.58) | 0.079 | |
| GAMA | 0.73 (0.58,0.83) | 0.0001 | 0.24 (−0.13,0.56) | 0.099 | |
| CYHA | 0.76 (0.63,0.85) | 0.0001 | 0.65 (0.37,0.82) | 0.0001 | |
| CYMA | 0.42 (0.18,0.61) | 0.0001 | 0.66 (0.4,0.83) | 0.0001 | |
| CEMA | 0.49 (0.27,0.66) | 0.0001 | 0.39 (0.04,0.66) | 0.016 | |
| HPMA | 0.27 (0.01,0.49) | 0.021 | 0.39 (0.03,0.66) | 0.016 | |
| BMA | 0.25 (0.00,0.48) | 0.025 | 0.42 (0.07,0.68) | 0.011 | |
| MADA | 0.37 (0.13,0.58) | 0.002 | 0.38 (0.02,0.65) | 0.021 | |
| PHGA | 0.23 (−0.02,0.46) | 0.036 | −0.5 (−0.73,−0.17) | 0.997 | |
| PMA | 0.07 (−0.19,0.32) | 0.29 | 0.18 (−0.2,0.51) | 0.176 | |
| HPM2 | 0.27 (0.02,0.49) | 0.018 | 0.41 (0.05,0.67) | 0.013 | |
| AMCA | 0.31 (0.05,0.52) | 0.009 | 0.43 (0.07,0.68) | 0.01 | |
| DHBM | 0.13 (−0.13,0.37) | 0.167 | −0.01 (−0.37,0.36) | 0.51 | |
| MHB3 | 0.11 (−0.15,0.36) | 0.197 | 0.45 (0.11,0.7) | 0.006 | |
| HPMM | 0.11 (−0.15,0.36) | 0.204 | 0.45 (0.08,0.71) | 0.009 | |
| IPM3 | 0.11 (−0.16,0.35) | 0.215 | 0.2 (−0.17,0.53) | 0.142 | |
| TTCA | 0.32 (0.07,0.53) | 0.007 | 0.39 (0.03,0.66) | 0.017 |