Screening for dementia: Brazilian version of the Informant Questionnaire on Cognitive Decline on the Elderly and its psychometric properties

• Published in: Geriatrics & gerontology international 2013-07, Vol.13 (3), p.687-693
• Main Authors: Sanchez, Maria Angélica dos Santos, Lourenço, Roberto Alves
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Brazil; Cognition & reasoning; Cognition - physiology; Cognition Disorders - diagnosis; Cognition Disorders - epidemiology; Cognition Disorders - psychology; cognitive neuroscience; Cross-Sectional Studies; Dementia; dementia - Alzheimer's disease; Dementia - diagnosis; Dementia - epidemiology; Dementia - psychology; diagnosis and classification; families; Female; Follow-Up Studies; Geriatric Assessment - methods; Humans; Male; Mass Screening - methods; Medical screening; memory; Older people; Prevalence; Psychiatric Status Rating Scales; Psychometrics - methods; Questionnaires; ROC Curve; Surveys and Questionnaires
• ISSN: 1444-1586; 1447-0594
• DOI: 10.1111/j.1447-0594.2012.00966.x

Aim To assess the criterion validity of the Brazilian version of the Informant Questionnaire on Cognitive Decline on the Elderly (IQCODE‐BR), and analyze the influence of educational level and age of both the elderly and the informants on the questionnaire scores. Method The study design was a cross‐sectional study with a convenience sample. Convergent validity was assessed using the Mini‐Mental State Examination, and the accuracy of the IQCODE‐BR was evaluated by receiver operating characteristic curve analysis. Multivariate logistic regression analysis was carried out to determine the influence of sociodemographic characteristics on IQCODE‐BR scores. Results A total of 169 elderly individuals participated in the study, of which 35.5% were diagnosed with dementia. There was no statistically significant association between the IQCODE‐BR scores, and the age and educational level of both the elderly and the informants. The cut‐off point for greater accuracy was 3.52, with sensitivity of 83.3% and specificity of 80.7%. The area under the receiver operating characteristic curve was 0.83 (95% CI 0.766–0.893). There was a negative and moderate correlation between IQCODE‐BR and the Mini‐Mental State Examination scores (P