Likelihood ratios & area under the curve quiz

Positive and negative likelihood ratios will vary dependant upon the prevalence of the disease in question?

Likelihood ratios can be used to calculate post test probabilities?

The magnitude of a likelihood ratio can be used to determine its significance?

When looking to develop a diagnostic test, the area under the curve can be used to help evaluate the utility of a test. An area under the curve of 1 means that the test will be no more useful than relying on chance.

If a patient has a pretest likelihood of disease of 10%, you apply a test gaining a positive result and you know the test to have a positive likelihood ratio of 5, the post test probability will be 50%?

A positive likelihood ratio is calculated by sensitivity/(1-specificity)?