Which test is appropriate for correlating categorical and continuous variables?

#1
Hi,
I'm looking to correlate a categorical variable (genetic risk for dyslexia: yes/no) with a few different continuos variables (rapid naming, letter knowledge, language skills), i.e. I want to know how genetic risk for dyslexia is correlated with the mentioned continuous variables. The data for rapid naming is normally distributed, the rest is not. Total sample size is 40 children. What would be the appropriate test to use? My supervisor told me that Spearman's rho is not appropriate and to use chi square, but after doing some reading it seems that chi square requires two categorical variables and is also not be appropriate. Grateful for any help :)
 

Karabiner

TS Contributor
#4
want to know how genetic risk for dyslexia is correlated with the mentioned continuous variables.
You can perform a series of t tests. These will tell you whether means of these variables differ bteween those with or without risk. You can also check how large the differences are in the sample.
The data for rapid naming is normally distributed, the rest is not.
Irrelevant . It sometimes matters whether data within groups are from normal distributions. But ony with n(total) < 30.

With kind regards

Karabiner