Screening and diagnostic tests
Screening identifies people who may have a condition before clinical recognition; confirmatory diagnosis is a separate clinical process and depends on pretest probability.
Open interactive lesson & self-check ↗Screening and diagnostic tests — learning map
Original conceptual SVG · scalableOriginal schematic relationship map for this topic; relationships are organized for study, not intended as an anatomical depiction or a diagnostic algorithm.
Sensitivity
Sensitivity is the proportion of people with the target condition who test positive in the defined population.
Specificity
Specificity is the proportion without the condition who test negative. Sensitivity and specificity can vary with case mix and threshold.
Predictive values
Positive and negative predictive values depend on both test performance and disease prevalence in the tested population.
Benefit and harm
Screening can cause false positives, overdiagnosis and follow-up harm; evidence of earlier diagnosis alone does not establish a population health benefit.
Reference and next reading
Explore the original curriculum and publisher-hosted resources for full-depth reading; this note is an original schematic introduction, not an exhaustive chapter.