19 min listen
Episode 39 - Likelihood Ratios
Episode 39 - Likelihood Ratios
ratings:
Length:
17 minutes
Released:
Dec 8, 2015
Format:
Podcast episode
Description
We cover Dr. Rory Spiegel's blog EMNERD, covering an article in Chest 2015 by Pivetta et al, discussing the ways lung ultrasound (US) may be far more helpful than the brain natriuretic peptide (BNP) in determining heart failure in the dyspneic patient.
Then we delve into likelihood ratios and show notes can be found at FOAMCAST.org
Bottom Line, LR of 1 is useless. It doesn't change the likelihood of using the disease.
+ LR >5 is good, + LR of 10 means that a test is useful and, if positive, patient most likely had the disease
- LR 0.2 is ok but a - LR of 0.1 is much more helpful.
Using a Fagan nomogran, one can understand how various likelihood ratios (and tests with their known LRs) may affect the post-test probability (i.e. the likelihood the patient has the disease). The utility of tests also depends on the pretest probability.
Then we delve into likelihood ratios and show notes can be found at FOAMCAST.org
Bottom Line, LR of 1 is useless. It doesn't change the likelihood of using the disease.
+ LR >5 is good, + LR of 10 means that a test is useful and, if positive, patient most likely had the disease
- LR 0.2 is ok but a - LR of 0.1 is much more helpful.
Using a Fagan nomogran, one can understand how various likelihood ratios (and tests with their known LRs) may affect the post-test probability (i.e. the likelihood the patient has the disease). The utility of tests also depends on the pretest probability.
Released:
Dec 8, 2015
Format:
Podcast episode
Titles in the series (100)
Episode #1: Cyanide and Carbon Monoxide Toxicity: An Emergency Medicine and Free Open Access Medical Education (FOAM) Core Content Review by FOAMcast - An Emergency Medicine Podcast