title: Dementia staging across three different methods.
abstract: OBJECTIVE
  To investigate the effectiveness of an item response theory (IRT)-based approach to staging dementia.
  
  
  METHODS
  IRT estimates of dementia severity in 1,485 patients were used to stage dementia and then compared to dementia staging using the classic Clinical Dementia Rating Scale (CDR) algorithm and the Sum of the Boxes (SOB) approach.
  
  
  RESULTS
  Measurement imprecision was highest when dementia stages were determined based on the classic algorithm (48% of sample), lower when they were determined based on the SOB approach (12%), and lowest when determined using IRT-based staging (0%).
  
  
  CONCLUSIONS
  The classic CDR algorithm weights boxes largely according to clinical experience. The SOB approach weights all boxes equally. The IRT approach weights boxes according to their actual ability to identify dementia severity and therefore provides the most precise information for staging dementia.
authors.affiliation: Texas A&M University, College Station, USA. balsis @ tamu.edu
authors.forename: Steve
authors.initials: S
authors.lastname: Balsis
authors.forename: Tyler M
authors.initials: TM
authors.lastname: Miller
authors.forename: Jared F
authors.initials: JF
authors.lastname: Benge
authors.forename: Rachelle S
authors.initials: RS
authors.lastname: Doody
mesh_terms: D000368:Aged; D000465:Algorithms; D000544:Alzheimer Disease / Q000175:diagnosis / Q000523:psychology; D003704:Dementia / Q000175:diagnosis* / Q000523:psychology; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales