Validation of the CAMCOG-DS-II, a neuropsychological test battery for Alzheimer's disease in people with Down syndrome: A Horizon 21 European Down syndrome Consortium study

Abstract

INTRODUCTION: The Cambridge Cognitive Examination modified for use in people with Down syndrome (CAMCOG-DS) is a sensitive cognitive test for Alzheimer’s disease (AD)–related decline in people with DS, but needs updates for sensitivity, cultural adaptability, and additional memory/executive function items. This study aimed to develop and validate the CAMCOG-DS-II. METHODS: In this multi-language, multi-site study, the psychometric properties of the CAMCOG-DS-II were evaluated against previously validated measures in 223 participants (mean age: 40.18 years) with DS across seven countries. RESULTS: The CAMCOG-DS-II had a high completion rate, minimal floor/ceiling effects (compared to the modified Cued Recall Test, the CANTAB Paired Associates Learning, and the Purdue Pegboard), strong validity and reliability, and performance was unaffected by language across sites. It differentiated between those with/without AD and distinguished clinically rated cognitively stable and prodromal individuals. CONCLUSION: The CAMCOG-DS-II is a sensitive measure of cognitive performance in people with DS at risk of AD. Its cross-language and site reliability support its potential use in AD–DS clinical trials.