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History of AFNI updates  

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April 30, 2021 10:11AM
G'day everyone,

I was wondering if someone could check if the contrasts that I've written for 3dLMEr are correct?
Our study is different than the examples put foreward in the help file, therefore I'm not 100% certain and would really appreciate some confirmation :)

The following model is for a longitudinal study with two groups and measurements after 0,2,4,... months.
We unfortunately have missing data, therefore using 3dLMEr :)

-prefix outputfile \
-jobs 12 \
-model  "Time*Group+Age+Gender+(1|Subj)" \
-qVars "Time,Age,outcome1,outcome2,outcome3" \
-resid residuals \
-mask mask.nii.gz \
(I specified more variables as qVars than I put into the model, because I might model them later on. That way I just need to change one line of code ;) )

The contrast I've specified for the effect of time on Group 1 vs Group 2:
-gltCode Group1-Group2_TimeEff 'Group : 1*Group1 -1*Group2 Time :' 			\

The effect of time for both groups separately:
-gltCode Group1_TimeEff 'Group : 1*Group1 Time :' 			\
-gltCode Group2_TimeEff 'Group : 1*Group2 Time :' 			\

The effect of Group at Time 0 (?):
-gltCode Group1-Group2 'Group : 1*Group1 -1*Group2' 			\


And last but not least: The effects of age and gender:
-gltCode Age 'Age :' 			\
-gltCode F-M 'Gender : 1*f -1*m' 			\

The data table looks like this:
Subj Group Time outcome1 outcome2 outcome3 outcome4 outcome5 InputFile
1 Group1 0 1.44 2.33 235 255 5 path/to/file.nii.gz

I'd be happy about some feedback :)

--Agent 007 ;)
Subject Author Posted

Contrasts for longitudinal 3dLMEr

AFNIuser007 April 30, 2021 10:11AM

Re: Contrasts for longitudinal 3dLMEr

gang May 01, 2021 08:44AM

Re: Contrasts for longitudinal 3dLMEr

AFNIuser007 May 01, 2021 11:53AM

Re: Contrasts for longitudinal 3dLMEr

gang May 01, 2021 04:37PM

Re: Contrasts for longitudinal 3dLMEr

AFNIuser007 May 01, 2021 09:00PM

Re: Contrasts for longitudinal 3dLMEr

gang May 02, 2021 09:00AM

Re: Contrasts for longitudinal 3dLMEr

AFNIuser007 May 02, 2021 10:30AM

Re: Contrasts for longitudinal 3dLMEr

AFNIuser007 May 13, 2021 12:31PM

Re: Contrasts for longitudinal 3dLMEr

gang May 13, 2021 10:12PM

Re: Contrasts for longitudinal 3dLMEr

AFNIuser007 May 16, 2021 07:07AM

Re: Contrasts for longitudinal 3dLMEr

gang May 17, 2021 07:34AM

Re: Contrasts for longitudinal 3dLMEr

AFNIuser007 May 25, 2021 03:37PM

Re: Contrasts for longitudinal 3dLMEr

gang May 26, 2021 01:06PM

Re: Contrasts for longitudinal 3dLMEr

AFNIuser007 May 27, 2021 04:11PM