Hi Guys, sorry if the question might sound stupid but I'm not sure about how to set a statistical test. Basically I have 2000 breast cancer patients that had surgery. Of them, 1000 had additional tumours (not secondary but primary tumours) divided according to the following classes.
ADDITIONAL Class A 50 Class B 250 Class C 450 Class D 250
The 1000 patients are further divided in pre-post surgery as follows:
PRE Class A 20 Class B 150 Class C 120 Class D 75 POST Class A 30 Class B 100 Class C 330 Class D 175
Now I would like to compare the dataset PRE with the dataset ADDITIONAL in order to see if there's some enrichment as well as the dataset POST with the dataset ADDITIONAL for the same reason. I already have compared the PRE-POST between them. I suppose I have to perform a Fisher test but I' m a little bit confused on how to write the contingency table. Can anyone help me please?
Thank you in advance