Supplementary Material for: Eye-tracking–based cognitive assessment efficiently detects mild cognitive decline in the predementia stage

Introduction: The early detection of cognitive decline is key to maximizing the benefits of preventive and therapeutic interventions against dementia. Generally, dementia is first assessed by interview-based neuropsychological tests, but the lengthy interview and mental stress during the assessment process make screenings inefficient. We previously developed a rapid screening test for dementia using an eye-tracking technology (eye tracking–based cognitive assessment, ETCA) and reported its utility for clinically detecting cognitive impairment in dementia cases. However, the ETCA’s performance in detecting people with mild cognitive decline, which is the major target population for dementia-prevention strategies, remains insufficiently examined. Therefore, this study aimed to evaluate the ETCA’s performance in individuals aged 40 years and older (n = 94, mean age; 61.0 [SD 13.1] years) without being formally diagnosed with dementia. Methods: All participants underwent both the ETCA and neuropsychological tests, including the Mini-Mental State Examination (MMSE), Rivermead Behavioral Memory Test (RBMT), and Addenbrooke’s Cognitive Examination-III (ACE-III) on the same day. We examined the correlations in scores between the ETCA and each neuropsychological test. Furthermore, we selected participants who earned normal scores in each neuropsychological test and evaluated the ETCA’s performance in this subgroup. Results: Participants’ ETCA scores correlated significantly with their scores on neuropsychological tests, including the MMSE, RBMT, and ACE-III. Notably, the ETCA scores correlated with the RBMT or ACE-III scores in individuals who showed normal scores in each neuropsychological test. Conclusion: The ETCA has the potential to screen mild cognitive decline efficiently at the predementia stage in nonclinical settings.