title: A brief dementia screener suitable for use by non-specialists in resource poor settings--the cross-cultural derivation and validation of the brief Community Screening Instrument for Dementia.
abstract: OBJECTIVE
  Brief screening tools for dementia for use by non-specialists in primary care have yet to be validated in non-western settings where cultural factors and limited education may complicate the task. We aimed to derive a brief version of cognitive and informant scales from the Community Screening Instrument for Dementia (CSI-D) and to carry out initial assessments of their likely validity.
  
  
  METHODS
  We applied Mokken analysis to CSI-D cognitive and informant scale data from 15 022 participants in representative population-based surveys in Latin America, India and China, to identify a subset of items from each that conformed optimally to item response theory scaling principles. The validity coefficients of the resulting brief scales (area under ROC curve, optimal cutpoint, sensitivity, specificity and Youden's index) were estimated from data collected in a previous cross-cultural validation of the full CSI-D.
  
  
  RESULTS
  Seven cognitive items (Loevinger H coefficient 0.64) and six informant items (Loevinger H coefficient 0.69) were selected with excellent hierarchical scaling properties. For the brief cognitive scale, AUROC varied between 0.88 and 0.97, for the brief informant scale between 0.92 and 1.00, and for the combined algorithm between 0.94 and 1.00. Optimal cutpoints did not vary between regions. Youden's index for the combined algorithm varied between 0.78 and 1.00 by region.
  
  
  CONCLUSIONS
  A brief version of the full CSI-D appears to share the favourable culture- and education-fair screening properties of the full assessment, despite considerable abbreviation. The feasibility and validity of the brief version still needs to be established in routine primary care.
authors.affiliation: Centre for Global Mental Health, Health Service and Population Research Department, King's College London, Institute of Psychiatry, UK. m.prince@iop.kcl.ac.uk
authors.forename: M
authors.initials: M
authors.lastname: Prince
authors.forename: D
authors.initials: D
authors.lastname: Acosta
authors.forename: C P
authors.initials: CP
authors.lastname: Ferri
authors.forename: M
authors.initials: M
authors.lastname: Guerra
authors.forename: Y
authors.initials: Y
authors.lastname: Huang
authors.forename: K S
authors.initials: KS
authors.lastname: Jacob
authors.forename: J J
authors.initials: JJ
authors.lastname: Llibre Rodriguez
authors.forename: A
authors.initials: A
authors.lastname: Salas
authors.forename: A L
authors.initials: AL
authors.lastname: Sosa
authors.forename: J D
authors.initials: JD
authors.lastname: Williams
authors.forename: K S
authors.initials: KS
authors.lastname: Hall
mesh_terms: D010054:Brief Psychiatric Rating Scale / Q000592:standards*; D002681:China; D003462:Cuba; D003466:Cultural Characteristics; D003704:Dementia / Q000175:diagnosis* / Q000523:psychology; D006801:Humans; D007194:India; D007843:Latin America; D009549:Nigeria; D010865:Pilot Projects; D015203:Reproducibility of Results; D012424:Rural Population; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires