C-statistics for receiver-operating characteristic analyses of baseline covariates alone and with addition of baseline biomarkers.

p-values are derived from unconditional logistic regression models, and reflect the statistical significance of the difference of the C-statistic in biomarker-added models, compared to the baseline covariates (reference) model. CC16 = Club Cell Protein 16, hsCRP = high sensitivity C-reactive protein, IL-6 = interleukin 6, SP-D = surfactant protein D.