I am working on a multi-level logistic regression (Binary Outcome) model and am trying to finding the best way to check the assumption of linearity for the continuous variables. I am using STATA and have tried lowess graphs using the logit option, Box-Tidwell, and the lincheck methods . All of these options have given somewhat conflicting results. Variables that appear to be linear using the lowess graphs are not considered linear according to Box-Tidwell or the lincheck methods. I know the lowess graphs are smoothed graphs so this maybe explains why they conflict. I am wondering what the most reliable or accepted method for checking linearity using STATA is. I am also familiar with SAS if someone knows a better method using that package.

Thanks