I am not a statistician, but a medical researcher and I have 5 outcomes that I want to identify independent predictor(s) for each using multiple regression. I have many potential variables that could be included in the multiple regression as independent variables (IV).
One colleague advises to run Spearman correlation matrix between all IV and DV, then to include only the significantly correlated IV in the multiple regression.
- Is it appropriate to include only significant predictors with significant bivariate spearman correlations with the outcome?
- Alternatively, what is a good way to determine inclusion of predictors in a multiple regression?