Yes, that looks right (assuming that cortisol is your first variable)
On 11/7/2023 3:49 PM, Laura Willers de Souza wrote:
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Hello FreeSurfer Developers,
Following the FSGD examples on the website, I built the following test:
Question: Is there an association between cortisol and cortical thickness regressing out the effect of sex, age, APOE4_carrier (1=1 or 2 alleles, 0=no alleles), abeta, ptau, diagnosis (CU and CI)? Regressors: 2 factors (sex, diagnosis) with 2 levels each, 5 covariates (age, APOE4_carrier (1=1 or 2 alleles, 0=no alleles), abeta, ptau, cortisol) >> 24 regressors Contrast: 0 0 0 0 0.5 -0.5 0.5 -0.5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 FSGD: GroupDescriptorFile 1 Title CSF_semgrupos Class MaleCU Class MaleCI Class FemaleCU Class FemaleCI Variables Cortisol Age ABETA ptau APOE4_carrier Input 098_S_4003_I224603 MaleCI 11 81.3 741.5 22.83 1
Does this feel right to you?
I am having difficulty understanding how to construct the contrast to answer the following question "Is the interaction between group (CU/CI) and cortisol significant regressing out the effect of sex, age, APOE_carrier, abeta and ptau?" It seems like the contrast would be the same as before.. Can you guys help me with this?
Thanks in advance!
*Laura Willers de Souza *
PhD Student in Pharmacology and Therapeutics
Zimmer Lab - Federal University of Rio Grande do Sul
- Porto Alegre/RS - Brazil
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