New IDEAS: Imaging Dementia-Evidence for Amyloid Scanning Study

Inclusion Criteria: * Medicare beneficiary with Medicare as primary insurance; * Meets clinical criteria for Mild Cognitive Impairment (MCI) or Dementia as defined by the 2018 National Institute on Aging - Alzheimer's Association Research Framework * Brain MRI and/or CT within 24 months prior to enrollment; * Clinical laboratory assessment (complete blood count \[CBC\], standard blood chemistry profile, thyroid stimulating hormone \[TSH\], vitamin B12) within the 12 months prior to enrollment; * Able to tolerate amyloid PET required by protocol, to be performed at a participating PET facility; * English or Spanish speaking (for the purposes of informed consent); * Willing and able to provide consent. Consent may be by proxy; * Neuropsychiatric syndrome can be classified into "clinically typical" or "clinically atypical" categories Exclusion Criteria: * Normal cognition or subjective complaints that are not verified by cognitive testing or key informant. * Knowledge of amyloid status, in the opinion of the referring dementia expert, may cause significant psychological harm or otherwise negatively impact the patient or family. * Amyloid status already known to patient or referring clinician based on prior amyloid imaging or cerebrospinal fluid analysis. * Current or previous enrollment in an anti-amyloid therapeutic trial. * Scan is being ordered solely based on a family history of dementia, presence of apolipoprotein E (ApoE) 4, or in lieu of genotyping for suspected autoso…