Youden Index for Optimal Cutpoints
A practical guide to the Youden Index for selecting optimal diagnostic and biomarker cutpoints, including ROC curves, sensitivity, specificity, threshold selection, worked examples, limitations, validation, and R implementation.
ROC Curve Analysis Explained
A practical guide to ROC curve analysis, including sensitivity, specificity, thresholds, AUC, Youden
Diagnostic Test Accuracy Meta-Analysis
A practical guide to diagnostic test accuracy meta-analysis, including sensitivity, specificity, likelihood ratios, diagnostic odds ratios, forest plots, ROC space, SROC curves, HSROC and bivariate models, heterogeneity, threshold effects, study design, data preparation, and R implementation.
Companion Diagnostic Statistical Validation
A practical guide to statistical validation of companion diagnostics, covering analytical accuracy, precision, reproducibility, sensitivity, specificity, limit of detection, reportable range, interference, robustness, clinical concordance, positive and negative percent agreement, confidence intervals, sample size, missing data, discordant results, and regulatory considerations.
Biomarker-Stratified Trial Designs
A practical guide to biomarker-stratified clinical trial designs, including stratified randomization, biomarker subgroups, predictive versus prognostic biomarkers, enrichment designs, treatment-by-biomarker interaction, sample size, multiplicity, missing biomarker status, statistical analysis, regulatory interpretation, and R implementation.