Odds Ratio

Odds Ratio, Hazard Ratio and Relative Risk

Odds ratio (OR) is a statistic commonly encountered in professional or scientific medical literature. Most readers perceive it as relative risk (RR), although most of them do not know why that would be true. But since such perception is mostly correct, there is nothing (or almost nothing) wrong with that. It is nevertheless useful to be reminded now and then what is the relation between the rel...

Prevalence odds ratio v prevalence ratio.

Statistics notes. The odds ratio.

In recent years odds ratios have become widely used in medical reports—almost certainly some will appear in today’s BMJ. There are three reasons for this. Firstly, they provide an estimate (with confidence interval) for the relationship between two binary (“yes or no”) variables. Secondly, they enable us to examine the effects of other variables on that relationship, using logistic regression. ...

Prevalence odds ratio versus prevalence ratio: choice comes with consequences.

Odds ratio, risk ratio, and prevalence ratio are some of the measures of association which are often reported in research studies quantifying the relationship between an independent variable and the outcome of interest. There has been much debate on the issue of which measure is appropriate to report depending on the study design. However, the literature on selecting a particular category of th...

Visualizing, Summarizing, and Comparing Odds Ratio Structures

The odds ratio is one of the main measures of association in 2× 2 tables. For larger tables, summary measures of association have been proposed as well as modeling strategies, where the odds ratios can be deduced from the parameters of a model. We propose a computationally simple scaling methodology, which gives a summary measure of association and a visualization of the odds ratio structure. D...