Screening & Diagnostic Tests

Summary

Develops screening and diagnostic test evaluation starting with the four-quadrant accuracy-precision diagram and measures including coefficient of variation, concordance correlation coefficient, Bland-Altman plots, and Cohen's kappa with its prevalence paradox and Landis-Koch interpretation scale. Builds the two-by-two table for sensitivity, specificity, false positives and false negatives, then introduces predictive values to show how a positive result's meaning depends on the underlying prevalence of disease in the tested population. Closes with receiver operating characteristic curves, likelihood ratios, and how to balance threshold choices against the asymmetric costs of missed cases versus false alarms.