Determining optimal cutoff scores of Cognitive Abilities Screening Instrument to identify dementia and mild cognitive impairment in Taiwan

Sep 17, 2026

Early detection of dementia relies on efficient cognitive assessment methods, yet existing cognitive screening tools often struggle to differentiate cognitive status, especially during early-stage impairment. This study analyzed 8,979 individuals over 50 years with unimpaired cognition, mild cognitive impairment (MCI), or dementia to identify optimal CASI cutoff values. CASI task performance was evaluated using Cox proportional hazards models for predicting conversion from MCI to all-cause dementia, Alzheimer’s-type dementia, and vascular dementia.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages11

Reading Time28 min

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Abstract

Background

Methods

Results

Conclusion

Introduction

Cognitive assessment challenges in early-stage dementia

Role of cognitive screening tests and CASI

Study aims and hypotheses

Methods

Participants

Lyu et al. BMC Geriatrics (2024) 24:216 [https://doi.org/10.1186/s12877-024-04810-y](https://doi.org/10.1186/s12877-024-04810-y) BMC Geriatrics RESEARCH Open Access Determining optimal cutoff scores of Cognitive Abilities Screening Instrument to identify dementia and mild cognitive impairment in Taiwan Wan‑Jing Lyu 1†, Pai‑Yi Chiu2†, Chung‑Hsiang Liu3, Yu‑Chi Liao 1 and Hsin‑Te Chang1,4,5* Abstract Background The early detection of dementia depends on efficient methods for the assessment of cognitive capac‑ ity. Existing cognitive screening tools are ill‑suited to the differentiation of cognitive status, particularly when dealing with early‑stage impairment. Methods The study included 8,979 individuals (> 50 years) with unimpaired cognitive functions, mild cognitive impairment (MCI), or dementia. This study sought to determine optimal cutoffs values for the Cognitive Abili‑ ties Screening Instrument (CASI) aimed at differentiating between individuals with or without dementia as well as between individuals with or without mild cognitive impairment. Cox proportional hazards models were used to evaluate the value of CASI tasks in predicting conversion from MCI to all‑cause dementia, dementia of Alzheimer’s type (DAT), or to vascular dementia (VaD) . Results Our optimized cutoff scores achieved high accuracy in differentiating between individuals with or with‑ out dementia (AUC = 0 .87—0. 93) and moderate accuracy in differentiating between CU and MCI individuals (AUC = 0.67 – 0 . 74) . Among individuals without cognitive impairment, scores that were at least 1.5 × the standard deviation below the mean scores on CASI memory tasks were predictive of conversion to dementia within roughly 2 years after the first assessment (all‑cause dementia: hazard ratio [HR] = 2.81 – 3. 53; DAT: 1.28 – 1.49; VaD: 1. 58) . Note that the cutoff scores derived in this study were lower than those reported in previous studies. Conclusion Our results in this study underline the importance of establishing optimal cutoff scores for individuals with specific demographic characteristics and establishing profiles by which to guide CASI analysis. Keywords Aging, Cognitive assessment, Cognitive disorders, Dementia, Memory †Wan‑Jing Lyu and Pai‑Yi Chiu contributed equally to this work. *Correspondence: Hsin‑Te Chang [changht@cycu.edu.tw](changht@cycu.edu.tw) Full list of author information is available at the end of the article © The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit [http://creativecommons.org/licenses/by/4.0/](http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver ()[. The Creative Commons Public Domain Dedication waiver (](http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver ()[http://creativecom](http://creativecom)‑ [mons.org/publicdomain/zero/1.0/](mons.org/publicdomain/zero/1.0/)) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Lyu et al. BMC Geriatrics (2024) 24:216 Introduction Determining the cognitive status of elderly individuals can be exceedingly difficult when dealing with early-stage dementi

FAQs

What problem does the study address about cognitive screening tools?

Existing cognitive screening tools are often ill-suited for differentiating cognitive status, particularly for early-stage impairment, motivating the search for better cutoff scores.

How many participants were included and who were they?

The study included 8,979 individuals older than 50 years across three groups: unimpaired cognition, mild cognitive impairment (MCI), and dementia.

What did the optimized CASI cutoff scores help predict?

Optimized cutoff scores supported differentiation between dementia and non-dementia and showed predictive value for conversion from MCI toward all-cause dementia, Alzheimer’s-type dementia (DAT), and vascular dementia (VaD).

Sep 17, 2026

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