Table 3.
PEth as Optimal Baseline Biomarker and Comparisons to Models With Additional Biomarkers
| Biomarker Model | AUROC (95%CI) | Continuous NRI (95% CI) | Continuous IDI (95% CI) |
|---|---|---|---|
| PEth Only Model | |||
| Imputed/log-transformed | 0.93 (0.90–0.96) | — | — |
| Complete Case Analysis | 0.93 (0.90–0.96) | — | — |
| PEth and BAC Model | |||
| Imputed/log-transformed | 0.93 (0.90–0.97) | 0.39 (0.13–0.62)* | 0.03 (0.01–0.05)* |
| Complete Case Analysis | 0.93 (0.90–0.97) | 0.82 (0.58–1.06)* | 0.06 (0.020–10)* |
| PEth and GGT Model | |||
| Imputed/log-transformed | 0.93 (0.89–0.96) | 0.23 (–0.03–0.48) | –0.02 (–0.04–0.00) |
| Complete Case Analysis | 0.92 (0.88–0.95) | 0.07 (–0.15–0.29) | 0.01 (–0.01–0.03) |
| PEth and CDT Model | |||
| Imputed/log-transformed | 0.93 (0.90–0.96 | 0.19 (–0.06–0.43) | –0.02 (–0.04–0.00) |
| Complete Case Analysis | 0.92 (0.88–0.96) | –0.08 (–0.36–0.20) | 0.01 (–0.01–0.02) |
| PEth and Urine EtG Model | |||
| Imputed/log-transformed | 0.94 (0.92–0.97) | 0.79 (0.55–1.03)* | 0.02 (0.01–0.04)* |
| Complete Case Analysis | 0.94 (0.91–0.97) | 0.45 (0.24–0.67)* | 0.03 (–0.01–0.07) |
| PEth and Urine EtS Model | |||
| Imputed/log-transformed | 0.94 (0.91–0.97) | 0.54 (0.31-0.78)* | 0.01 (–0.01–0.02) |
| Complete Case Analysis | 0.94 (0.91–0.97) | 0.45 (0.24-0.67)* | 0.03 (–0.01–0.07) |
| Multivariable Model | |||
| PEth + BAC + GGT + CDT | |||
| Imputed/log-transformed | 0.93 (0.90–0.97) | –0.04 (–0.3–0.23) | 0.00 (–0.01–0.02) |
| Complete Case Analysis | 0.90 (0.85–0.95) | 0.67 (0.41–0.94)* | 0.07 (0.02–0.12)* |
P < 0.05.
%CDT, percent serum carbohydrate deficient transferrin. Complete case analysis of 4-variable model after cross-validated selection operation for selecting biomarkers across imputed and long-transformed datasets. Complete case analysis of 4-variable model with sample size n = 208. Multivariable model selected after LASSO performed on multiply imputed datasets and variable important averaged. Both EtG and EtS add nearly no importance and were excluded from the final selection of combination biomarkers for evaluation.
AUROC indicates area under the receiver operating characteristic curve; EtG, urine ethyl glucuronide normalized with urinary creatinine; EtS, urine ethyl sulfate normalized for urinary creatinine; GGT, serum gamma-glutamyl-transpeptidase; IDI, integrated discrimination index; NRI, net reclassification index; PEth, phosphatidylethanol 16:0/18:1.