Before revision:  Similar results of low reliabilitywere found when comparing rescan sessions of the same subjects, and even between different FreeSurfer versions of the same scans. To understand our observations of low reliability, we estimated a measurement error covariance, and we show that it is largest in cortical thickness.
After revision:  Similar results of low reliabilitywere found when comparing rescan sessions of the same subjects, and even between different FreeSurfer versions of the same image. We could further estimate the relative measurement error and showed that it is largest in cortical thickness.