Statistical Tests

On the USMLE, you will most likely be presented with a research design and according to the variables, you will be asked which statistical test to use.

 

2 interval variables: Pearson's correlation

2 ordinal variables: Spearman correlation
2 nominal variables: Chi-square
Both nominal and interval variables:

• 2 groups: t-test
• more than 2 groups: ANOVA

A mnemonic for interval vs. nominal is PINK:
Pearson = Interval
Nominal = Khi square (Chi square)