HI,

I have 3 groups of randomly assigned subjects and measuring dependent variable at 2 time points, before intervention (pre-test) and after intervention (post-test). I was thinking about doing ANCOVA with pretest value as co-variate. Or should I use rANOVA instead?

Should I compare pretest values with ANOVA to see if there are significant differences first?

My dependent variables are on continuous scale (mm, msec...)

And I was thinking in presenting change from baseline values for descriptive statistics. Percents or absolute values?

Similar questions and discussions