Cultural Adaptation and Validation of the Alzheimer’s Disease Assessment Scale – Cognitive Subscale (ADAS-Cog) - Kannada Version for a South Indian population

Abstract

Background: At present there a few culturally adapted and validated standardised neuropsychological tests for detection of persons with dementia in low-and middle income countries. Therefore, we conducted an adaptation, validation and feasibility study of the Alzheimer’s disease Assessment Scale – Cognitive Subscale (ADAS-Cog) in Kannada for use among older adults. Methods: two panels set up involving participants, subject experts and other important stakeholders. Several structured qualitative interviews informed the process of cultural adaptations (structure, content and language) the ADAS-Cog-Kannada. For the purpose of validation 120 men and women (58 of them had mild to moderate dementia and 62 of them were age and gender matched controls) were recruited. Concurrent validity was evaluated against the 10/66 Battery of Cognitive Tests in Kannada. Results: The ADAS-Cog-Kannada demonstrated internal consistency and concurrent validity. Sensitivity and Specificity for ADAS-Cog Kannada (score>14) for diagnosis of dementia were 85% and 92% respectively. It was feasible to administer ADAS-Cog in a standardised manner among community dwelling older adults and took an average of 30 minutes to administer. Conclusion: ADAS-Cog was adapted to Kannada and evaluated by employing robust methods resulting in an instrument that we believe is now culturally acceptable. Psychometric properties of ADAS-Cog Kannada were strong and linguistically acceptable. It can be used in clinical setting among Kannada speaking population and the culturally adapted.