Hello,
I have two sample randomized in function two methods to reduce pain.
The variable analysed is the scale of pain « EVA » (numeric discret variable : 1, 2, 3,... to 10).
I create a new variable : EVA < 4 with code 1 (and EVA > or = is coded 0).
There is a qualitative nominal variable in function type of chirurgical intervention : orthopedic, digestive,...
How can I make a Chi square test to analyse the EVA < 4 in function the arm of randomisation in a SUB SAMPLE (ex in patient underwent orthopedic intervention) ?
Thank you +++