From time to time, our PET Quality Control process identifies data as faulty that have already been posted and downloaded by users. We are not able to notify individual investigators of these problems. Therefore, any investigators working with PET data should regularly check the following site for notification of faulty data, and this data should be removed from all analyses until it has been corrected and reposted. For more information on PET scan advisories contact: Robert Koeppe, ADNI PET Core QC Coordinator (koeppe@umich.edu)