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Dear Freesurfer experts, 

Hope everyone is doing well! Could someone please clarify some things about mris_anatomical_stats, done after running qdec + mapping label to all subjects? 
From what I can  understand, the following code should be used: 

mris_anatomical_stats -l lh.supramarg.label \
  -t lh.thickness -b -f 004/stats/lh.supramarg.stats 004 lh

But if I created the ".label" file directly on qdec, by "mapping label to all subjects", and didn't use the mri_label2label code for "target subjects", how should I work around this to perform mris_anatomical_stat correctly? 
Also, I'm confused on when + where this "lh.thickness" file is created and stored. 
Please let me know if you need any other information about my code or my qdec output. 

Thank you, 
Alex Job Said