jamovi

Hi everybody, I'm facing an issue with the t-test.
I'm trying to compare how blood tests change in some patients, according to their previous therapies.
Some patients used biologic therapies before (some used drug A, some others drug B, some others drug C), some other did not use them at all before.

My aim is to compare two groups: the group who used drug A and/or C before vs patients who did not use biologic therapies at all before.

I already created a new variable meshing all together the patients who used drug A and/or C.

Hope somebody could help, thank you very much in advance

sounds like you're on the right track ... you'll be wanting to use an "independent samples t-test".

one column will contain the measure of interest (your dependent variable) and one column will contain their group (those having used biologic therapies before, and those who haven't).

if you want to run an analogous analysis, use the Tooth Growth data set in the data library, and see if there's an effect on Tooth Length (len, dependent variable), of supplement (vitamin C vs orange juice, dose, grouping variable).

jonathon