title: Differentiating between demented and psychiatric patients with the Dutch version of the IQCODE.
abstract: This study presents psychometric data on the Dutch version of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE-N). We focused on differentiating between inpatients with dementia or a mood/psychotic disorder. A cutoff point of 3.9 on the IQCODE-N correctly predicted group membership in 87.8% and 78.8% respectively. Internal consistency and principal component analysis suggest that the IQCODE-N measures a unidimensional construct. Correlations with a Dementia Screening Test (r = 0.62), nurses' observations on memory disorders (r = 0.71) and a global assessment of severity of dementia (r = 0.72) support the validity of the informant ratings. Patients' age and level of education did not confound informant ratings. Only a small fraction of the informants could not complete the IQCODE-N, which makes it an easily applicable rating scale for cognitive decline.
authors.affiliation: Psychiatric Hospital Vogelenzang, Bennebroek, The Netherlands.
authors.forename: J F
authors.initials: JF
authors.lastname: de Jonghe
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D003704:Dementia / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005163:Factor Analysis, Statistical; D005260:Female; D005852:Geriatric Psychiatry / Q000379:methods*; D006801:Humans; D008297:Male; D009426:Netherlands; D011569:Psychiatric Status Rating Scales / Q000592:standards*; D011594:Psychometrics / Q000592:standards*; D011618:Psychotic Disorders / Q000175:diagnosis*; D015203:Reproducibility of Results; D012720:Severity of Illness Index