6 Aug
2013
6 Aug
'13
6 p.m.
Hello,
I am measuring the changes of subcortical volumes in a longitudinal study, so I took the volumes from longitudinal subjects (/name.long.base/). Now we need to perform the correction using the eTIV parameter, but the eTIV for longitudinal subjects for all time points is the same (/i//.e. eTIV for subject-time1.long.base = eTIV for subject-time2.long.base/)
Is it correct to perform the correction using the eTIV values from the longitudinal subjects, or we should use these measures from the cross-sectional corresponding subjects ?
Thanks,
Alex.