Dear all,
I know that this is a subject that has come up once or twice, but I
can't seem to find a direct answer to my query in the archives.
The query is with regard to normalisation in the optimsed method. I am
performing analyses on 50 patient and (versus) 50 control scans. Do I:
(1) normalise the patient GM images to a mean GM image constructed
from the normlised, segmented and smoothed patient scans from the
standard protocol, whilst normalising control GM img files to a mean
control image constructed in the same way, or
(2) normalise all individual patients and controls to a mean GM image
constructed from all patients and controls?
How would (1) affect the comparisons?
What effects would (2) have on the results?
I hope that this was clear!
Thanks and best wishes,
Simon
Simon S Keller
The Magnetic Resonance and Image Analysis Research Centre (MARIARC)
University of Liverpool
Pembroke Place
Liverpool, L69 3BX
Tel: 0151 794 5634
Fax: 0151 794 5635
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