yes, that is the correct interpretation
On 7/16/2022 1:00 PM, Boa Sorte Silva, Narlon wrote:
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Dear experts,
I am conducting a group analysis and wanted to confirm that the set up below accurately addresses our research question. Thanks for your help, much appreciated!
Background:
- We have two groups (intervention vs control) and two timepoints (pre vs post)
- Our data have already been processed and stacked with *long_mris_slopes* where pc1 is the measure of interest (post - pre).
- Our covariates are sex (male vs female), age, and MMSE scores.
- Thus, our model has 4 groups (2 factors/2 levels): o int_male o int_female o con_male o con_female
- We’re using *DODS*
- We’re running the analysis with *mri_glmfit* in the Longitudinal Two Stage Model
As such, we want test whether there are greater changes in the intervention group vs control group in the pc1 measure, adjusting for the influence of sex, age, and MMSE.
This is our FSGD:
GroupDescriptorFile 1
Title Between-group
Class int_male
Class int_female
Class con_male
Class con_female
Variables age mmse
Input 001.MR int_male 30 25
Input 002.MR int_female 40 22
Input 003.MR con_male 60 29
Input 004.MR con_female 60 21
…
And this is the contrast matrix
+0.5 +0.5 -0.5 -0.5 +0 +0 +0 +0 +0 +0 +0 +0
With the above contrast matrix, our interpretation would be:
- Intervention > control = positive result
- Intervention < control = negative result
Is this the correct set up and interpretation?
Thanks for taking the time,
Best regards,
Nárlon Cássio
*Nárlon Cássio Boa Sorte Silva* PhD (He, Him, His)
CIHR and MSHR BC/PARF Postdoctoral Research Fellow
Aging, Mobility, and Cognitive Health Lab
Djavad Mowafaghian Centre for Brain Health
Department of Physical Therapy, Faculty of Medicine
University of British Columbia
Vancouver, Canada
Twitter: @BoaNarlon
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