Population normative data for the 10/66 Dementia Research Group cognitive test battery from Latin America, India and China: a cross-sectional survey
1 National Institute of Neurology and Neurosurgery of Mexico, Mexico City, Mexico
2 King's College London (Institute of Psychiatry), London, UK
3 Universidad Nacional Pedro Henriquez Ureña (UNPHU), Santo Domingo, Dominican Republic
4 Instituto de la Memoria y Desórdenes Relacionados, Universidad Peruana Cayetano Heredia,. Lima, Peru
5 Institute of Mental Health, Peking University, Beijing, PR China
6 Christian Medical College, Vellore, India
7 Facultad de Medicina Finley-Albarran, Medical University of Havana, Cuba
8 Caracas University Hospital Faculty of Medicine, Universidad Central de Venezuela, Caracas, Venezuela
9 Clínica Loira, Caracas, Venezuela
10 Community Health Services, VHS, Chennai, India
11 Dirección General de Salud Publica Ministerio de Protección Social (6th district), Santo Domingo, Dominican Republic
BMC Neurology 2009, 9:48 doi:10.1186/1471-2377-9-48Published: 26 August 2009
1) To report site-specific normative values by age, sex and educational level for four components of the 10/66 Dementia Research Group cognitive test battery; 2) to estimate the main and interactive effects of age, sex, and educational level by site; and 3) to investigate the effect of site by region and by rural or urban location.
Population-based cross-sectional one phase catchment area surveys were conducted in Cuba, Dominican Republic, Venezuela, Peru, Mexico, China and India. The protocol included the administration of the Community Screening Instrument for Dementia (CSI 'D', generating the COGSCORE measure of global function), and the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) verbal fluency (VF), word list memory (WLM, immediate recall) and recall (WLR, delayed recall) tests. Only those free of dementia were included in the analysis.
Older people, and those with less education performed worse on all four tests. The effect of sex was much smaller and less consistent. There was a considerable effect of site after accounting for compositional differences in age, education and sex. Much of this was accounted for by the effect of region with Chinese participants performing better, and Indian participants worse, than those from Latin America. The effect of region was more prominent for VF and WLM than for COGSCORE and WLR.
Cognitive assessment is a basic element for dementia diagnosis. Age- and education-specific norms are required for this purpose, while the effect of gender can probably be ignored. The basis of cultural effects is poorly understood, but our findings serve to emphasise that normative data may not be safely generalised from one population to another with quite different characteristics. The minimal effects of region on COGSCORE and WLR are reassuring with respect to the cross-cultural validity of the 10/66 dementia diagnosis, which uses only these elements of the 10/66 battery.