Fig. 3

Calibration curves for the nomogram model in the derivation (A) and validation (B) cohorts. The x-axis represents the forecasted TBM risk, whereas the actual diagnosed TBM is shown on the y-axis. For each subsequent decile, the observed TBM rate in the cohort was plotted against the model prediction (black circle, average; grey line, 95% CI). The diagonal dotted line represents the ideal model with perfect prediction ability, and the solid line (bias-corrected line) represents the real performance of the nomogram. The closer the fit to the diagonal dotted line, the better the prediction ability of the nomogram. The nomogram model was excellently calibrated in both derivation and validation cohorts. AUC: area under the curve, CI: confidence interval, TBM: tuberculous meningitis