# In medical statistics, when to use $\chi^2$ and when to use Kruskal-Wallis H?

I am conducting a retrospective analysis on the effect of three different treatment option (intervention treatment) on a special type of cancer, so I have three groups: 1, 2, and 3.

In the baseline patient demographic table for the three groups, I have multiple variables like age, gender, presence of other disease, presence of lymph node involvement, etc. All of them are coded categorical variables (0,1), I want to know if there is a significant difference in each variable for the three groups.

Some articles use the Chi-Squared test and others use Kruskal-Wallis H test.

Which one is the correct one? Or if there is another possibility?