Department of Long-Term Care, National Taipei University of Nursing and Health Sciences, Taipei.
Department of Health Industry Management, Kainan University, Taoyuan, Taiwan.
Medicine (Baltimore). 2021 Mar 19;100(11):e25225. doi: 10.1097/MD.0000000000025225.
The Cognitive Abilities Screening Instrument (CASI) assesses global cognitive function in people with dementia with 9 domains (i.e., long-term memory, short-term memory, concentration, orientation, attention, abstraction and judgment, language abilities, visual construction, and category fluency). However, the ecological, convergent, and discriminant validities of the CASI have not yet been examined.
This study designed to investigate these 3 validities of the CASI in people with dementia.
Fifty-eight participants underwent assessments with the CASI, 3 functional measures, and 3 cognitive measures. Pearson's r was used to estimate correlations among the CASI and 3 functional measures for examining ecological validity. We computed correlations (r) among the CASI and 3 functional measures for examining convergent validity. An independent t-test was applied to compare the levels of disability, and ceiling/floor effects were analyzed for examining discriminative validity.
The CASI total score and domains had moderate to high correlations with 3 functional measures (r = 0.42-0.80), except in 2 CASI domains (i.e., attention and language). The CASI total score and domains showed moderate to high correlations with 3 cognitive measures (r = 0.45-0.93). The t-test results revealed significant differences (P < .05) in the CASI total score and other domains except for the short-term memory domains. Four domains of the CASI showed noticeable ceiling effects (22.4-39.7%).
The CASI has adequate ecological validity, good convergent validity, and acceptable discriminative validity in people with dementia. The 5 domains with nonsignificant differences or ceiling effects should only be used with caution to distinguish people with dementia.
认知能力筛查工具（CASI）通过 9 个领域（即长期记忆、短期记忆、注意力、定向、注意力、抽象和判断、语言能力、视觉构建和类别流畅性）评估痴呆患者的整体认知功能。然而，CASI 的生态、收敛和判别有效性尚未得到检验。
本研究旨在探讨痴呆患者 CASI 的这 3 种有效性。
58 名参与者接受了 CASI、3 项功能评估和 3 项认知评估。使用 Pearson r 来估计 CASI 与 3 项功能评估之间的相关性，以检验生态有效性。我们计算了 CASI 与 3 项功能评估之间的相关性（r），以检验收敛有效性。应用独立 t 检验比较残疾水平，并分析天花板/地板效应以检验判别有效性。
CASI 总分和各领域与 3 项功能评估（r=0.42-0.80）具有中度至高度相关性，除了 CASI 的 2 个领域（即注意力和语言）。CASI 总分和各领域与 3 项认知评估（r=0.45-0.93）具有中度至高度相关性。t 检验结果表明，除了短期记忆领域外，CASI 总分和其他领域存在显著差异（P<.05）。CASI 的 4 个领域存在明显的天花板效应（22.4%-39.7%）。
CASI 在痴呆患者中具有足够的生态有效性、良好的收敛有效性和可接受的判别有效性。5 个领域没有显著差异或天花板效应，应该谨慎使用，以区分痴呆患者。
