title: Do Beliefs about the Pathogenetic Role of Amyloid Affect the Interpretation of Amyloid PET in the Clinic.
abstract: BACKGROUND
  Beliefs of dementia experts about the pathogenic role of amyloid in Alzheimer's disease (AD) may affect the use of amyloid positron emission tomography (PET).
  
  
  OBJECTIVE
  To assess the role attributed to amyloid in AD pathogenesis by Italian dementia experts, and whether this modulates the impact of amyloid PET results in their diagnostic workup.
  
  
  METHODS
  22 dementia experts rated their beliefs about the pathogenic role of amyloid. Then, we asked them to rate the probability of change in diagnosis based on the result of amyloid PET for 7 case vignettes, depicting patients who initially received a diagnosis based on a comprehensive workup and later received amyloid PET results consistent or inconsistent with the clinical picture.
  
  
  RESULTS
  55% of the experts assigned a dominant role to amyloid, and 32% attributed a similar role to amyloid and tau in AD pathogenesis. The probability of change in diagnosis ranged from 17% (SD = 21.6) for cases with consistent to 51% (SD = 34) for cases with inconsistent PET versus clinical data. Diagnostic change was not biased by the clinicians' beliefs about AD pathogenesis.
  
  
  CONCLUSIONS
  This work supports an unbiased interpretation of amyloid PET across different beliefs about the pathogenic role of amyloid, and a belief-independent reluctance to change diagnosis in cases where change is expected and recommended.
authors.affiliation: Laboratory of Alzheimer's Neuroimaging and Epidemiology, IRCCS Fatebenefratelli, University of Brescia, Brescia, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Boccardi
authors.forename: Daniele
authors.initials: D
authors.lastname: Altomare
authors.forename: Clarissa
authors.initials: C
authors.lastname: Ferrari
authors.forename: Cristina
authors.initials: C
authors.lastname: Festari
authors.forename: Luigi
authors.initials: L
authors.lastname: Antelmi
authors.forename: Michela
authors.initials: M
authors.lastname: Pievani
authors.forename: Anna
authors.initials: A
authors.lastname: Tarallo
authors.forename: Cristina
authors.initials: C
authors.lastname: Muscio
authors.forename: Ugo P
authors.initials: UP
authors.lastname: Guerra
authors.forename: Barbara
authors.initials: B
authors.lastname: Paghera
authors.forename: Alessandro
authors.initials: A
authors.lastname: Padovani
authors.forename: Giovanni B
authors.initials: GB
authors.lastname: Frisoni
mesh_terms: D000544:Alzheimer Disease / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000378:metabolism; D000682:Amyloid / Q000378:metabolism*; D001291:Attitude of Health Personnel; D003937:Diagnosis, Differential; D006801:Humans; D007558:Italy; D010820:Physicians / Q000523:psychology*; D010865:Pilot Projects; D049268:Positron-Emission Tomography / Q000523:psychology*; D016875:tau Proteins / Q000378:metabolism
chemical_list: D000682:Amyloid; C054369:MAPT protein, human; D016875:tau Proteins