Re: Can I compare two within-subjects' dependent variables while holding co-variates?

Posted by NHR on Dec 19, 2011; 4:21pm
URL: http://spssx-discussion.165.s1.nabble.com/Can-I-compare-two-within-subjects-dependent-variables-while-holding-co-variates-tp5085591p5086603.html

Hi,
Thanks a lot for your replay.

My dependent variables are PTSD measures. I have 3 sub-scales and one total measure. These 4 measures refer to two different events, so each participant has 8 measures (4 for every event - 4 couples).

I wanted to compare, for example the degree of avoidance symptoms between event 1 and 2, and so on, regarding each couple. Each participant has 2 marks/grads, for each measure - one for every event.
But, than I wand to hold as co-variates the time duration that passed since each event. I wanted to do that cause there is a significant difference between the time duration that passed between the two events.
While doing an ANOVA or MANOVA, the two co-variates (duration since each event) influence the two dependent variables, and that is no good. I thinks there is no point in holding as co-variate the duration since event 1 while looking at the symptomolgy after event 2.
So, I was wondering how can I compare my dependent variables in a better way?

The participants were all volunteers, who agreed to participate in a web-survey.


I hope my answers are clear.
Please let me know if not, and I'll be happy to answer.

Thanks a lot,
I really appreciate it,
NHR