Likelihood Ratios (LR+ & LR-)

Defines diagnostic likelihood ratios (LR+ & LR-), how they are used, and how to calculate them. Also describes how to use LR+ and LR- to move from pre-test probability to post-test probability of disease.

*Learning Objectives*
0:00 Define the Likelihood Ratio (LR).
1:22 Relate the value of the Likelihood Ratio (LR) to its effect on the final decision to treat or not to treat a patient.
2:42 Calculate both the Positive Likelihood Ratio (LR+) and the Negative Likelihood Ratio (LR-) using sensitivity (Sn) and specificity (Sp).
3:21 Evaluate the usefulness of a diagnostic test result by interpreting both the *LR+* (e.g., *greater than 10*) and the *LR-* (e.g., *less than 0.1*).

Видео Likelihood Ratios (LR+ & LR-) канала Ruth Lilly Medical Library