The Dépistage Cognitif de Québec: A New Clinician's Tool for Early Recognition of Atypical Dementia

Dement Geriatr Cogn Disord. 2018;46(5-6):310-321. doi: 10.1159/000494348. Epub 2018 Nov 27.


Introduction: Early recognition of atypical dementia remains challenging partly because of lack of cognitive screening instruments precisely tailored for this purpose.

Methods: We assessed the validity and reliability of the Dépistage Cognitif de Québec (DCQ;, a newly developed cognitive screening test, to detect atypical dementia using a multicenter cohort of 628 participants. Sensitivity and specificity were compared to the Montreal Cognitive Assessment (MoCA). A predictive diagnostic algorithm for atypical dementia was determined using classification tree analysis.

Results: The DCQ showed excellent psychometric properties. It was significantly more accurate than the MoCA to detect atypical dementia. All correlations between DCQ indexes and standard neuropsychological measures were significant. A statistical model distinguished typical from atypical dementia with a predictive power of 79%.

Discussion: The DCQ is a better tool to detect atypical dementia than standard cognitive screening tests. Expanding the clinician's tool kit with the DCQ could reduce missed/delayed identification of atypical dementia and accelerate therapeutic intervention.

Keywords: Alzheimer’s disease; Alzheimer’s variants; Atypical dementia; Cognitive assessment; Frontotemporal dementia; Frontotemporal lobar degeneration spectrum; Logopenic primary progressive aphasia; Neurocognitive disorders; Neurocognitive testing; Posterior cortical atrophy; Primary progressive aphasia; Screening tools.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cohort Studies
  • Dementia* / diagnosis
  • Dementia* / psychology
  • Diagnostic Errors / prevention & control*
  • Early Diagnosis
  • Female
  • Geriatric Assessment / methods
  • Humans
  • Male
  • Mental Status and Dementia Tests*
  • Neuropsychological Tests
  • Quebec
  • Reproducibility of Results
  • Sensitivity and Specificity