Hello,

I have mixed model, where I evaluated on univariant analysis by either Pearson for categorical variables or logistic regression for continuous variables significance to a binary outcome (eg mortality).

Putting those variables (continuous and categorical) into a multivariate analysis shows me a certain effect, using "Fit Model" and "Nominal Logistic" option with subsequent manual backward elimination until all p<0.05.

Now, some statistician friends told me, I cannot use categorical and continous variables in the same multivariate analysis, and should rather categorize my continuous variables into categorical variables (eg split by interquartile ranges) and use those, only categorical variables in the multivariate regression. Or vice versa, I should exclude my categorical variables in the model and use only continuous variables.

What do people think ? - Any advice much appreciated. Many thanks, Marc