Thank you all very much. These information are very helpful.
Jin
Quoting Cyrus Raji <[log in to unmask]>:
> Marko,
>
> Ah, this is very interesting! So what it sounds like you are saying is that
> one could construct a custom elderly template that statistically accounts
> for, for instance, the burden of co-morbid psychiatric disease or some other
> confounder.
>
> Thank you,
>
> Cyrus
>
> On Fri, Jan 16, 2009 at 3:16 AM, Marko Wilke <
> [log in to unmask]> wrote:
>
>> 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
>>
>> --
>> =====================================================================
>> 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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