One IV (2levels) 4 DVS - What test to use?

#1
Hi all,

Asked a question on this forum previously and the response is far greater than any other forum around!
I have been collecting pre and post data for a psychological treatment 4 pre and 4 post data points (they are repeated meaures) for 500 clients, measured as Scale. The clients are also allocated to one of two treatment types, coded as 1 and 2 Nominal. The study will be treated as quasi-experimental.

I know that there is a sig difference between Intake and discharge, for all treatment types, but what I want to test is the difference between Treatments (the IV). I expect that there will be no sig diff here, which is good for my study. I am using the DASS (Depression, Anxiety, Stress scale) and wanted to know whether I should be testing a measure of change (DIscharge minus Intake) to be comparing these means?

My issue is that I am so rusty that I am forgetting which test that I need to use in particular, I am pretty sure multi variate.

If you have any questions let me know and I will do my best to answer anything
 

Karabiner

TS Contributor
#2
I know that there is a sig difference between Intake and discharge, for all treatment types, but what I want to test is the difference between Treatments
Repeated measures (or "mixed") ANOVA, with time (pre vs.post) as
within-subjects factor and treatment as grouping factor. The time x group
interaction will show whether the changes from pre to post were different
between groups.

With kind regards

K.
 
#3
Repeated measures (or "mixed") ANOVA, with time (pre vs.post) as
within-subjects factor and treatment as grouping factor. The time x group
interaction will show whether the changes from pre to post were different
between groups.
Thank you so much! Is there a guide that I can follow to do this, I am using SPSS 19.
 
#5
Sorry to be a pain, but I really need some help with the above, I'm an independent researcher with no ability to bounce these questions off. Any thoughts?
 

nbjo

New Member
#6
Just too make sure, you have 8 different time points? The graphs produced will be the most useful to examine.

First, recode your treatment/experimental variable to 0 (control) and 1 (treatment), I will refer to it as GROUP.

In SPSS, go to GLM -> Repeated Measures
Label the within-subject factor SCALE
Indicate 8 levels
Define them as each time point (make sure they are in order, TIME1, TIME2, ... TIME8).
Add GROUP as a between subjects factor.

There are other options you can check for sig. tests, descriptive stats, etc.
I HIGHLY recommend you go into Plots and add SCALE to the horizontal axis with separate plot for GROUP.

You will get a full factorial output.
SCALE
GROUP
SCALE * GROUP (or labeled the opposite)


Repeat this process for each DV.

For more output interpretation help, I need more specifics. Hope this helps and best of luck!