Analysis of the Addenbrooke’s Cognitive Examination using the Rasch Model

Abstract

The Addenbrooke's Cognitive Examination (ACE) is a brief cognitive test, recently validated in Spain, designed to distinguish between Alzheimer's disease and frontotemporal dementia. In this study we evaluated the psychometric properties of the Spanish version of ACE using the Rasch model and the discriminative performance of the test was compared with the Mini-Mental State Examination (MMSE). The test was applied to a group of 103 participants, 53 of whom had previously received a diagnosis of dementia. Results indicate that, in general, ACE has adequate psychometric properties for test items and the overall measurement, although test performance is influenced by some sociodemographic characteristics of participants (gender and educational level). Moreover, compared with the MMSE, ACE items identify a broader set of cognitive impairment symptoms and it has greater discrimination power. In conclusion, the Spanish version of the ACE seems to be a suitable tool for the diagnosis of dementia, although further research is needed to deepen its psychometric characteristics.