Ecological, convergent, and discriminative validities of the cognitive abilities screening instrument in people with dementia

摘要

BACKGROUND: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.PURPOSE:This study designed to investigate these 3 validities of the CASI in people with dementia.METHODS: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.RESULTS: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%).CONCLUSIONS: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.Copyright ? 2021 the Author(s). Published by Wolters Kluwer Health, Inc.