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Thanks, Anderson for your detailed response. I'll try these approaches and see how the correlation will work. The pre-term and term infants were imaged at 38 weeks of age. Yes, pre-term infants were age corrected according to our NICU critea. Thanks, Supreet On Fri, Aug 9, 2013 at 10:47 AM, Anderson M. Winkler <[log in to unmask] > wrote: > Hi Supreet, > > I think this is covered by the manual: > http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/GLM > > In particular, have a look at these two examples: > - > http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/GLM#Single-Group_Average_with_Additional_Covariate > - > http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/GLM#Two_Groups_with_continuous_covariate_interaction > > The first you can use for the analysis of the pre-term only (no comparison > with the term infants). In this example, the second contrast will show > where the DTI measures are associated with the BSITD scores. > > The second example you can use for the comparison of the relationship > between BSITD and DTI between the groups, i.e., whether BSITD and DTI > relate differently to each other for the different groups. > > And of course, you can also use > http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/GLM#Two-Group_Difference_Adjusted_for_Covariate > The first two contrasts in this example will tell if the groups differ in > their DTI measures taking BSITD into account as a nuisance (I don't think > this interests you much) and the remaining two contrasts tell whether and > where BSITD changes are associated with changes in the DTI measures after > taking into account the fact that the infant was born pre-term or at term. > > This all assumes that the scores are in sync with the MRI (you still > didn't mention whether the MRI was before birth or after). Also, it isn't > clear whether "scores were taken at term" means that the scores were taken > at birth or at some point around 38-40 weeks even if born weeks earlier. In > any case, if you corrected the scores using a method that is valid and well > accepted, then the above examples should work fine for you. > > Hope this helps! > > All the best, > > Anderson > > > > On 9 August 2013 14:46, Supreet kaur <[log in to unmask]> wrote: > >> Thanks, Anderson for your prompt response. I have BSITD scores for per >> subject (41 pre-terms (less than 32 weeks) and 16 full-term infants (38 >> weeks), the pre-term have been age >> corrected and these scores were taken at term. I have each individual >> score for corresponding infant. First, I am planning to just correlate the >> pre-term infants scores with their FA and then MD images. >> >> Then in the next analysis, I'd like to do the group comparison between >> pre-term and term infants' DTI measures and their corresponding scores. Is >> it possible to do these analysis in randomize? >> I'd appreciate your help. >> Thanks, >> Supreet. >> >> >> >> On Fri, Aug 9, 2013 at 9:19 AM, Anderson M. Winkler < >> [log in to unmask]> wrote: >> >>> Hi Supreet, >>> >>> >>> On 9 August 2013 13:42, Supreet kaur <[log in to unmask]> wrote: >>> >>>> >>>> Dear FSL experts, >>>> >>>> I would like to perform the voxelwise cross subject statistics to >>>> assess the relationship between FA, AD, and RD and performance scores of >>>> the infants (pre-terms and term infants) BSITD-III for our DTI cohort. I >>>> have two concerns: >>>> >>> >>> I guess you scanned both groups (pre-term and term) after they were >>> born, is this correct? Or did you scan them before birth and you'd like to >>> compare with BSITD obtained after? >>> >>> >>> 1) For applying the tbss on the non-FA images (I want to input the MD >>>> images), how do I input all the subject MD images? after I am done with >>>> the tbss analysis on the FA data. Is >>>> inside the tbss, does the tbss_non_FA command will automatically read >>>> it as non-FA images? >>>> >>> >>> Have you checked this page: >>> http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/TBSS/UserGuide#Using_non-FA_Images_in_TBSS >>> >>> >>> 2) For the randomize, since I'll be correlating the pre-term infant's FA >>>> and MD images to their mean BSITD-III scores,how can I incorporate the >>>> BSITD-III scores inside the model? is it going to be the paired t test or >>>> unpaired one? >>>> >>> >>> You need to give more information. How many BSITD scores do you have per >>> subject to take the mean? Do you have a matching image for each of these >>> scores for each subject, or just one image per infant? At which ages were >>> they (scores and/or images) taken? Are you going to check the relationship >>> with the MRI measures only for the pre-term or for both groups? >>> >>> Depending on what you have and what you'd like to do, the design is >>> going to be different. >>> >>> All the best, >>> >>> Anderson >>> >>> >>> >>>> >>>> I'd highly appreciate your feedback on this. >>>> >>>> >>>> >>>> Sincerely, >>>> >>>> Supreet >>>> >>> >>> >> >> >> -- >> Sincerely, >> >> Supreet kaur, >> Biomedical research engineer, >> Nationwide Childrens Hospital, >> Columbus, OH >> (614)355-3509 >> > > -- Sincerely, Supreet kaur, Biomedical research engineer, Nationwide Childrens Hospital, Columbus, OH (614)355-3509