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Dear Alex, Torben, Philipp, Ged, Thanks for all of your replies. I should have known that there is no way around what I wanted to avoid: trying it myself. Torben was right in that there are a few scaling and offset issues, but that templates are very similar (I will not post my results as I don't have time to make a proper presentation). Ged (and Torben off-list) made a really useful and relevant point about introducing a nuisance covariate for the two "scanners", which, by the way, in my case did NOT make the results less significant. Thanks again, Best wishes, Helmut ----- Original Message ----- From: "Ged Ridgway" <[log in to unmask]> To: <[log in to unmask]> Cc: <[log in to unmask]> Sent: Monday, July 02, 2007 2:03 PM Subject: Re: [SPM] SPM2 vs. SPM5 normalized template > Hi Helmut, > > I agree with all of Philipp's and Alex's comments; one minor thing I'd > mention... > >> ***If*** 1=yes and 2=satisfactory, and if there are no format problems, >> then off the top of my head I can’t see much of a problem (as shocking as >> it sounds). Knowing you, you will of course check for any systematic >> differences between the two preprocessing pathways… and I hope the two >> groups don’t correspond to patients versus controls etc. > > Maybe it would be worth including a covariate to indicate processing > pathway? Rather like the suggestion here > > http://en.wikibooks.org/wiki/SPM-VBM#Data_from_different_scanners > > Then your results will be (correctly) less significant the more correlated > the processing pathway indicator variable is to the effect of interest. > > Best, > Ged >