Test-Treatment Threshold Simulator

Ordering a diagnostic test is itself a decision, and clinical decision analysis gives it exact math. This simulator renders the Pauker-Kassirer probability axis as a 3D threshold bar: drag a patient's pretest probability of disease along it, tune the test's sensitivity and specificity and the relative benefit/harm of treatment, and watch two computed thresholds split the bar into three zones — skip the work-up, order the test, or treat empirically without testing. Markers show where a positive or a negative result would carry the patient's probability, so you can see directly whether the test result could plausibly change what you'd do next.