Proc GLM WELCH one-tailed test

[User423350]

Hi! I am using the proc glm welch option in order to implement a welch anova analysis. Is this test one-tailed or two-tailed?

This is the type of code i am using:

proc glm;
        class trt;
        model y = trt;
        means trt / hovtest=levene welch;
        run;

Thank you! 

[PaigeMiller]

I think this is a two-sided test, as are all tests in ANOVA.

[User423350]

How can i make the test one-tailed?