I imagine it will have some systematic effect. If your design is such that the two scan types are divided across your contrast of interest (eg, diagnosis), then including it as a nuisance regressor is probably fine.
On 1/3/19 4:31 PM, Arsenije Subotic wrote:
External Email - Use CautionDear experts,
For our study, we are planning on combining two different datasets to examine cortical thickness. There is a slight difference in the inversion time (400 vs 650) and flip angle ( 8 vs 11) between the two datasets. I know that free surfer measurements are fairly consistent across different scanner types and strengths, but do you know if slight differences in mri sequence parameters have an affect on cortical thickness? I was planning on adding it as a covariate in our analysis just in case.
Thank you! Arsenije
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