Skip to content

Episode Notes

USMLE purpose: Rapid-review a single biostats shortcut in Anki-card style.

How to use this page

  1. Identify whether the question is about disease status or test result.
  2. Choose sensitivity/specificity vs PPV/NPV.
  3. Open the toggle to confirm.
Episode metadata
FieldDetails
EpisodeRandy Neil Biostats 32
TopicBiostats short
Runtime1 min
Published2024-02-04
SourceOpen YouTube video

One-liner

If disease status is known first, think sensitivity/specificity; if test result is known first, think PPV/NPV.

Disease present → test positive?

Sensitivity.

Test positive → disease present?

Positive predictive value.

Extra practice

A question says, “Among patients with disease, how many test positive?” Which metric is this?

Reveal answer & explanation

Sensitivity. Disease status is known first, and the question asks whether the test catches it.