Hi Cyrus, Jin,
> At our institution we use a custom elderly template of 419 brains with
> an average age of about 70 years. Of course there's no rule I know of
> saying how many you have to use for the template but we tried using as
> many as possible to broadly reflect the general population.
I agree that there is no definite number that can be said to always
result in a "good" template, as 1, there is no measure of a good
template, and 2, it will depend on your input population. We recently
looked at the effect of increasing group sizes in our template-o-matic
paper (http://dx.doi.org/10.1016/j.neuroimage.2008.02.056) and found
clear effects of increasing group sizes from 12 to 48
Incidentally ;) this toolbox may also be of interest when you want to
generate a statistically defined, instead of an average, template for
special populations - it was designed to work on pediatric data but may
also be quite valuable in an elderly population.
Best,
Marko
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Marko Wilke (Dr.med./M.D.)
[log in to unmask]
Universitäts-Kinderklinik University Children's Hospital
Abt. III (Neuropädiatrie) Dept. III (Pediatric neurology)
Hoppe-Seyler-Str. 1, D - 72076 Tübingen
Tel.: (+49) 07071 29-83416 Fax: (+49) 07071 29-5473
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