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Dear Freesurfer experts,
I would like to know if this procedure is correct.
I have cortical thickness data from aparc+aseg for every ROI in DTK atlas (i.e. output of recon-all). I need average cortical thickness in frontal, parietal, temporal, cingulate and occipital lobes. Is it correct to average thickness measurement of every sub lobe roi (e.g. average thickness in frontal lobe = average of: 
  • Superior Frontal
  • Rostral and Caudal Middle Frontal
  • Pars Opercularis, Pars Triangularis, and Pars Orbitalis
  • Lateral and Medial Orbitofrontal
  • Precentral
  • Paracentral
  • Frontal Pole
and so on for other lobes... 

Do we need to correct for the number of vertices in every region when we measure the lobar average thickness?

Alternatively, do I need to run these commands to generate lobes then measure thickness in every lobe?
# mri_annotation2label --subject subject --hemi lh --lobesStrict lobes
# mri_annotation2label --subject subject --hemi rh --lobesStrict lobes
# mri_aparc2aseg --s subject --labelwm --hypo-as-wm --rip-unknown \
#   --volmask --o wmparc.lobes.mgz --ctxseg aparc+aseg.mgz \
#   --annot lobes --base-offset 200 [--base-offset must be last arg]

Thank you
James