Consider the variable vital status (STA) as the outcome variable and the remainder of the variables in the ICU data set as potential covariates. Use each of the variable selection methods discussed in this chapter to find a "best" model. Document thoroughly the rationale for each step in each process you follow. Compare and contrast the models resulting from the different approaches to variable selection. Note that in all cases the analysis should ad-

dress not only identification of main effects but also appropriate scale for continuous covariates and potential interactions. Display the results of your final model in a table. Include in the table point and 95% CI estimates of all relevant odds ratios. Document the rationale for choosing the final model.