Potashman, M., Pang, M., Tahir, M. et al. (4 more authors) (2023) Psychometric properties of the Alzheimer’s disease cooperative study – Activities of daily living for mild cognitive Impairment (ADCS-MCI-ADL) scale: a post hoc analysis of the ADCS ADC-008 trial. BMC Geriatrics, 23. 124. ISSN 1471-2318
Abstract
Background The Alzheimer's Disease Cooperative Study – Activities of Daily Living Scale for use in Mild Cognitive Impairment (MCI), the ADCS-ADL-MCI, is an evaluation scale with information provided by an informant/caregiver to describe the functional impairment of patients with MCI. As the ADCS-ADL-MCI has yet to undergo a full psychometric evaluation, this study aimed to evaluate the measurement properties of the ADCS-ADL-MCI in subjects with amnestic MCI.
Methods Measurement properties, including item-level analysis, internal consistency reliability, test–retest reliability, construct validity (convergent/discriminant, known-groups validity), and responsiveness were evaluated using data from the ADCS ADC-008 trial, a 36-month, multicenter, placebo-controlled study in 769 subjects with amnestic MCI (defined by clinical criteria and a global clinical dementia rating, CDR, score of 0.5). Due to most subjects' mild condition at baseline and resulting low variance in scores, psychometric properties were assessed using both baseline and 36-month data.
Results Ceiling effects were not apparent at the total score level, with 3% of the cohort reaching the maximum score of 53, despite most subjects having a relatively high score at baseline (mean score = 46.0 [standard deviation = 4.8]). Item-total correlations were overall weak at baseline, most likely due to low variability in responses; however, at month 36, good item homogeneity was found. Cronbach's alpha values ranged from acceptable (0.64 at baseline) to good (0.87 at month 36), indicating overall very good internal consistency reliability. Further, moderate to good test–retest reliability was found (intraclass correlation coefficients ranging from 0.62–0.73). The analyses also largely supported convergent/discriminant validity, especially at month 36. Finally, the ADCS-ADL-MCI discriminated well between groups showing good known-groups validity, and was responsive in patients who indicated a longitudinal change in other instruments.
Conclusions This study provides a comprehensive psychometric evaluation of the ADCS-ADL-MCI. Findings suggest that the ADCS-ADL-MCI is a reliable, valid and responsive measure capable of capturing functional abilities in patients with amnestic MCI.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Author(s) 2023. 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/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. |
Keywords: | ADCS-ADL-MCI; Activities of daily living; Alzheimer's Disease; Cognitive rating scale; Functional decline; Functional rating scale; Mild Cognitive Impairment; Outcome measure; Proxy-report; Psychometrics; Humans; Alzheimer Disease; Activities of Daily Living; Psychometrics; Reproducibility of Results; Cognitive Dysfunction |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Medicine, Dentistry and Health (Sheffield) > Department of Neuroscience (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 16 Mar 2023 11:00 |
Last Modified: | 16 Mar 2023 11:00 |
Published Version: | http://dx.doi.org/10.1186/s12877-022-03527-0 |
Status: | Published |
Publisher: | Springer Science and Business Media LLC |
Refereed: | Yes |
Identification Number: | 10.1186/s12877-022-03527-0 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:197321 |