Definitions for "Likelihood Ratio"
The ratio of a likelihood function for an unknown parameter vector to the likelihood function calculated at the estimated parameter vector. The relationship of this ratio to the chi-squared distribution can then be used to calculate confidence bounds and confidence regions.
An operator defined as the percentage of patients positive by gold standard for a particular disease, condition or injury who have a particular test result divided by the percentage of patients without the problem who have that same test result. A likelihood ratio of two means that the test result in question is twice as likely to come a patient with the problem as it is from a patient without the problem. The LR may be derived from reported sensitivity and specificity or from a clear understanding of the above definition. To see how the LR is used, see Bayes‘ Theorem; to actually use it, see the nomogram. To see how the Likelihood Ratio is generated, use the calculator
Ratio of the probability that a given diagnostic test result will be expected for a patient with the target disorder rather than for a patient without the disorder. ( Diagnosis) To Calculation