Dear experts,
Looking at the dataset 'adnimerge' I found a lot of subjects without information on the 'FLDSTRENG' field, although they have other MRI information (FSVERSION, ROI volumes, etc). Where I can find this missing information?
Thanks,
Best,
Silvia
You can refer to the variable FSVERSION. Based on the corresponding data file, it looks like FreeSurfer version 4.3 is all 1.5T. If you see an RID>2000 (so a newly recruited ADNI-GO or ADNI-2 participant), the field strength is 3T, since that was the protocol for ADNI-GO and ADNI-2.