Hi all,
How many levels can you incorporate into a multilevel model in SAS proc mixed? Can you have four, e.g. measurements over time nested within patients nested within providers nested within clinics?
Thanks for your help.
Yes, you can have four levels of nested effects. I don't think there is a maximum though keep in mind that PROC MIXED uses iterative estimation algorithm and large number of levels may substantially increase the computation time.
ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.