Hi,
> Maybe someone has tackled this with simulations? It sounds like the kind of thing Matthew Brett would do ;-)?
Well, just because my name was mentioned...
> As for your reviewer, ok, you may be losing some sensitivity but if you're involved in ongoing / long-term studies you might actually have had a reason to have stuck to somewhat dated software - and the improvements I've seen are moderate not revolutionary (say 1/15 individuals more in terms of detection rate) so while it's certainly reasonable to acknowledge the possibility of reduced sensitivity it seems a bit harsh to me to trash a study for it (if that's what's happened)...
I must say, like Alex, I would be astonished if the sensitivity
differences at the group level were anything other than small, and it
seems to me that your reviewer's comment is rather pedantic... I
doubt very much that most of the community would say you have to
reanalyze your data in SPM5 rather than SPM99 in order to trust the
results - unless you had hit a specific flaw in SPM99 - and it doesn't
sound like you have here.
My only specific experience is reanalyzing a study with 27 subjects
using the optimized VBM procedure (like SPM5) instead of the standard
SPM2 normalization; there was very little difference in the overall
results.
Best,
Matthew
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