Show Menu
Cheatography

Quantitative Methods Cheat Sheet (DRAFT) by

Relative Risks, Odds Ratios and Hypothesis Testing

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Relative Risk (RR)

What is it?
It measures the ratio of risk of outcome in exposed group to the risk in the unexposed group.

Study type
Cohort or Observ­ational studies

Formula
[A/(A+B)]/ [C/(C+D)]

Interp­ret­ation
The risk of the outcome is X times higher­/lower in those exposed than the risk in those unexposed.

Example
RR= 1.5
Unvacc­inated children were 1.5 times more likely to develop chickenpox than children who were vaccinated
 

Odds Ratio (OR)

 
Compares odds of an outcome in exposed vs unexposed group.

Study type
Case-C­ontrol

Formula
(A x D)/ (B x C)

Interp­ret­ation
The odds of the outcome in those exposed is X times the odds in those unexposed.

Example
OR =2.5
The odds of hypert­ension among adults who consume a lot of salt is 2.5 times the odds of hypert­ension among those who do not take in salt.
 

P-Value

 

P-value