Terheyden, J.H., Pondorfer, S.G., Behning, C. et al. (12 more authors) (2023) Disease-specific assessment of Vision Impairment in Low Luminance (VILL) in age-related macular degeneration – a MACUSTAR study report. British Journal of Ophthalmology, 107 (8). pp. 1144-1150. ISSN 0007-1161
Abstract
Background/Aims: To further validate the Vision Impairment in Low Luminance (VILL) questionnaire, which captures visual functioning and vision-related quality of life under low luminance, low contrast conditions relevant to age-related macular degeneration (AMD).
Methods: The VILL was translated from German into English (UK), Danish, Dutch, French, Italian and Portuguese. Rasch analysis was used to assess psychometric characteristics of 716 participants (65% female, mean age 72±7 years, 82% intermediate AMD) from the baseline visit of the MACUSTAR study. In a sub-set of participants (n=301), test-retest reliability (intra-class correlation coefficient, ICC; coefficient of repeatability, CoR) and construct validity were assessed.
Results: Four items were removed from the VILL-37 due to misfit. The resulting VILL-33 has three subscales with no disordered thresholds and no misfitting items. No differential item functioning and no multidimensionality were observed. Person reliability and person separation index were 0.91 and 3.27 for the reading subscale (VILL-R), 0.87 and 2.58 for the mobility subscale (VILL-M) and 0.78 and 1.90 for the emotional subscale (VILL-E). ICC and CoR were 0.92 and 1.9 for VILL-R, 0.93 and 1.8 for VILL-M and 0.82 and 5.0 for VILL-E. Reported visionrelated quality of life decreased with advanced AMD stage (p<0.0001) and was lower in the intermediate AMD group than in the no AMD group (p≤0.0053).
Conclusion: The VILL is a psychometrically sound patient-reported outcome instrument and the results further support its reliability and validity across all AMD stages. We recommend the shortened version of the questionnaire with three subscales (VILL-33) for future use.
Trial registration number NCT03349801.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2022 Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ. (https://creativecommons.org/licenses/by/4.0/) This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See: https://creativecommons.org/licenses/by/4.0/. |
Keywords: | Vision-related quality of life; age-related macular degeneration; patient-reported outcome; low luminance vision; psychometric assessment |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Medicine, Dentistry and Health (Sheffield) > School of Health and Related Research (Sheffield) > ScHARR - Sheffield Centre for Health and Related Research |
Funding Information: | Funder Grant number EUROPEAN COMMISSION - HORIZON 2020 116076 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 21 Mar 2022 17:19 |
Last Modified: | 28 Jun 2024 11:11 |
Status: | Published |
Publisher: | BMJ Publishing Group |
Refereed: | Yes |
Identification Number: | 10.1136/bjophthalmol-2021-320848 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:184728 |