A brief note about likelihood ratios

A brief note about likelihood ratios.

In this issue of the journal, Azzam and colleagues review the validation study of a clinical prediction rule for termination of resuscitation in patients suffering an out-of-hospital cardiac arrest. The clinical prediction rule is similar to a diagnostic test in that it predicts whether or not the patient will suffer the disorder of interest, in this case death, before hospital discharge. Given...

A Brief Note About Rott Contraction

One of the ways to model contraction functions for belief sets is epistemic entrenchment. The first step was provided by Gärdenfors in [5], who defined epistemic entrenchment and a contraction function in terms of it and related the latter with the AGM contraction function. Later Hans Rott in [16] presented an entrenchment based contraction function that does not satisfy recovery. In this paper...

Inferences for Likelihood Ratios

Likelihood ratios are extensively used to evaluate the performances of diagnostic tests and to update prior odds of disease to posttest odds. Since few tests are truly 100% accurate, including many used as “gold standards,” it is important to be able to estimate likelihood ratios in cases where no such standard is available. In this paper, methods to calculate point and interval estimates for l...

The trouble with likelihood ratios.

ity scale for clinicians is symmetrically skewed in both directions. In primary care, elective surgery, and oncology, clinicians work at the extremes of the probability scale. The time has come to apply the Feynman-Tufte principle to clinical logic, to offer a visual representation of Bayesian logic. Earlier attempts with natural logarithmics do not allow a simple graphic. We teach a scale of l...

Simplified calculations using likelihood ratios.