

D1. Check covariate model (continued) Three examples of covariate output are provided here. They differ in the number of treatment factors. Choose single if you only have one treatment factor, double if you have two (factorial, splitplot, stripplot, repeated measures), and triple if you have a splitsplitplot.
For example, the standard analysis: Be aware that if interactions of covariate with treatment are included, you are switching to "dummy" regression, and you may want to study such models under the Regression tab. If all tests are nonsignificant, then the standard covariate model is appropriate, and you can go back to Step D.

H I N T S : 
Remember, data transformations can fix apparent outliers. 
Do not be concerned if you have to rerun your SAS analysis many times. Correction of diagnostics may take several tries. 
To see an example using two covariates, see the Examples resource. 
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