 |
 |
Hi Matt, I don't understand this design, but yes, the only thing that needs to be changed is swap the sign. If the model is correct in one direction, it will be correct the other too. Also, yes, works same way irrespective to the imaging modality (FA, MD, etc). All the best, Anderson On 23 October 2015 at 18:35, Matthew Walton <[log in to unmask]> wrote: > Excellent thanks for your help, > > So if I want to compare leftward FA asymmetry to some measure of interest > with a few controls would this work? > > Measure | Control1|Control2| > +1 0 0 > > > And then this for rightward? > Measure | Control1|Control2| > -1 0 0 > > And this would obviously be the same for any other DTI measure (MD,AD,RD)? > > Thanks, > > Matt > > > On Fri, Oct 23, 2015 at 1:19 AM, Anderson M. Winkler < > [log in to unmask]> wrote: > >> Hi Matt, >> >> There are various ways, and perhaps the simplest is simply swap the sign >> of the contrast so you don't have to actually make changes to the images. >> In other words, in the contrasts, where values are positive, replace for >> negative, and vice-versa. >> >> All the best, >> >> Anderson >> >> >> On 22 October 2015 at 21:55, Matthew Walton <[log in to unmask]> >> wrote: >> >>> Hello, >>> >>> I've run through the basic TBSS pipeline, as well as tbss_sym. I'm just >>> a little confused as to how to go about changing symmetry results to test >>> for R>L (or rightward asymmetry if you will). >>> >>> The user guide says to "invert the data and rerun randomize". >>> What data is this referring to? Is there any other steps involved? >>> >>> Thanks for your help, >>> >>> Matt >>> >>> On Thu, Oct 22, 2015 at 12:27 PM, Matthew Walton < >>> [log in to unmask]> wrote: >>> >>>> Hello, >>>> >>>> I've run through the basic TBSS pipeline, as well as tbss_sym. I'm just >>>> a little confused as to how to go about changing symmetry results to test >>>> for R>L (or rightward asymmetry if you will). >>>> >>>> The user guide says to "invert the data and rerun randomize". >>>> What data is this referring to? Is there any other steps involved? >>>> >>>> Thanks for your help, >>>> >>>> Matt >>>> >>> >>> >> >