Dear all,

I want to include the original T-map of one study for the calculation of a whole-brain gray matter meta-analysis. The conversion process went well. However, I am unsure how to proceed now.

I can't include the T-map in the "Preprocessing-Step" as SDM is looking for txt-files. Thus, I went on to estimate the T-maps for the remaining studies and did copy the conversed T-map in the same folder, while also adding the study to SDM-table. However, doing so always results in a crash of the "sdm_core.exe". What am I missing?

In addition, I would like to know whethere there is a rule of thumb for the "number of randomizations" during preprocessing?


Any advice would be greatly appreciated. Thank you very much in advance.

Dear user

You should include the T map in the pre-processing step, the same way you include the text files. Note that for each study, SDM pre-processing looks for a T map with the name of the study (e.g. "smith2009.nii.gz") and, in case there is not, looks for text files (e.g. "smith2009.mni.txt").

Regarding the number of randomizations, stable results are achieved with less than 20 (Radua et al, Eur Psychiatry. 2012), so that 50 should be enough.

Best wishes,