Flinders University Flinders Academic Commons

Flinders Academic Commons >
Research Flagships, Centres and Institutes >
Flinders Centre for Ophthalmology, Eye and Vision Research >
Konrad Pesudovs >

Please use this identifier to cite or link to this item: http://hdl.handle.net/2328/995

Title: The usefulness of Vistech and FACT contrast sensitivity charts for cataract and refractive surgery outcomes research
Authors: Pesudovs, Konrad
Hazel, C A
Doran, R M L
Elliott, David B
Keywords: Cataract
Cataract Extraction
Comparative Study
Contrast Sensitivity
Factor Analysis, Statistical
Keratomileusis, Laser In Situ
Reproducibility of Results
Research Support, Non-U.S. Gov't
Sensitivity and Specificity
Treatment Outcome
Vision Tests
Visual Acuity
Issue Date: Jan-2004
Publisher: BMJ Publishing Group - http://bjo.bmjjournals.com/
Citation: K Pesudovs, CA Hazel, RML Doran and DB Elliott 2004. The Usefulness of Vistech and FACT contrast sensitivity charts for cataract and refractive surgery outcomes research. 'British Journal of Ophthalmology, January, Vol. 88, No. 1, 11-6
Abstract: AIM: To investigate the repeatability and sensitivity of two commonly used sine wave patch charts for contrast sensitivity (CS) measurement in cataract and refractive surgery outcomes. METHODS: The Vistech CS chart and its descendant, the Functional Acuity Contrast Test (FACT), were administered in three experiments: (1) Post-LASIK and age matched normal subjects; (2) Preoperative cataract surgery and age matched normal subjects; (3) Test-retest repeatability data in normal subjects. RESULTS: Contrast sensitivity was similar between post-LASIK and control groups and between the Vistech and FACT charts. The percentage of subjects one month post-LASIK achieving the maximum score across spatial frequencies (1.5, 3, 6, 12, 18 cycles per degree) were (50, 33, 13, 13, 0 respectively) for FACT, but only (0, 0, 13, 4, 0 respectively) for Vistech. A small number of cataract patients also registered the maximum score on the FACT, but up to 60% did not achieve the minimum score. Test-retest intraclass correlation coefficients varied from 0.28 to 0.64 for Vistech and 0.18 to 0.45 for FACT. Bland-Altman limits of agreement across spatial frequencies were between +/-0.30 and +/-0.85 logCS for Vistech, and +/-0.30 to +/-0.75 logCS for FACT. DISCUSSION: The Vistech was confirmed as providing poorly repeatable data. The FACT chart, likely because of a smaller step size, showed slightly better retest agreement. However, the reduced range of scores on the chart due to the smaller step size led to ceiling (post-LASIK) and floor (cataract) effects. These problems could mask subtle differences between groups of patients with near normal visual function as found post-refractive or cataract surgery. The Vistech and FACT CS charts are ill suited for refractive or cataract surgery outcomes research.
URI: http://hdl.handle.net/2328/995
ISSN: 0007-1161
Appears in Collections:Konrad Pesudovs

Files in This Item:

File Description SizeFormat
Pesudovs 2004 FACT download.pdf306.01 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.


Valid XHTML 1.0! DSpace Software Copyright © 2002-2010  Duraspace - Feedback