Validity and cultural generalisability of a 5-minute AI-based, computerised cognitive assessment in Mild Cognitive Impairment and Alzheimer's Dementia

Kalafatis, C.; Modarres, H.; Apostolou, P.; Marefat, H.; Khanbagi, M.; Karimi, H.; Vahabi, Z.; Aarsland, D.; Khaligh-Razavi, S.-M.

doi:10.1101/2021.04.01.437840

bioRxiv · 10.1101/2021.04.01.437840

Validity and cultural generalisability of a 5-minute AI-based, computerised cognitive assessment in Mild Cognitive Impairment and Alzheimer's Dementia

Kalafatis, C.·Modarres, H.·Apostolou, P.·Marefat, H.·Khanbagi, M.·Karimi, H.·Vahabi, Z.·Aarsland, D.·Khaligh-Razavi, S.-M.

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Abstract

INTRODUCTIONEarly detection and monitoring of mild cognitive impairment (MCI) and Alzheimers Disease (AD) patients are key to tackling dementia and providing benefits to patients, caregivers, healthcare providers and society. We developed the Integrated Cognitive Assessment (ICA); a 5-minute, language independent computerised cognitive test that employs an Artificial Intelligence (AI) model to improve its accuracy in detecting cognitive impairment. In this study, we aimed to evaluate the generalisability of the ICA in detecting cognitive impairment in MCI and mild AD patients. METHODSWe studied the ICA in a total of 230 participants. 95 healthy volunteers, 80 MCI, and 55 participants with mild AD completed the ICA, the Montreal Cognitive Assessment (MoCA) and Addenbrookes Cognitive Examination (ACE) cognitive tests. RESULTSThe ICA demonstrated convergent validity with MoCA (Pearson r = 0.58, p<0.0001) and ACE (r = 0.62, p<0.0001). The ICA AI model was able to detect cognitive impairment with an AUC of 81% for MCI patients, and 88% for mild AD patients. The AI model demonstrated improved performance with increased training data and showed generalisability in performance from one population to another. The ICA correlation of 0.17 (p=0.01) with education years is considerably smaller than that of MoCA (r=0.34, p<0.0001) and ACE (r=0.41, p<0.0001) which displayed significant correlations. In a separate study the ICA demonstrated no significant practice effect observed over the duration of the study. DISCUSSIONThe ICA can support clinicians by aiding accurate diagnosis of MCI and AD and is appropriate for large-scale screening of cognitive impairment. The ICA is unbiased by differences in language, culture and education.

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Kalafatis, C., Modarres, H., Apostolou, P., Marefat, H., Khanbagi, M., Karimi, H., Vahabi, Z., Aarsland, D., Khaligh-Razavi, S.-M.. 2021-04-02. Validity and cultural generalisability of a 5-minute AI-based, computerised cognitive assessment in Mild Cognitive Impairment and Alzheimer's Dementia. https://doi.org/10.1101/2021.04.01.437840

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