Dear experts,
We performed a multi-centre study and acquired T1-weighted scans from 180 controls and 180 patients. All controls and 78 patients were scanned at site 1, 24 patients in site 2, 48 in site 3, and 30 in site 4. We want to analyse grey matter volume in different networks, but find a bias for “centre” or "scanner", respectively. All scanners are 3T. What could be the cause and how can I correct for that? Any ideas are welcome.
Many Thanks,
Marisa
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