IOVS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Originally published In Press as doi:10.1167/iovs.08-1893 on May 23, 2008
 (Investigative Ophthalmology and Visual Science. 2008;49:4284-4289.)
© 2008 by The Association for Research in Vision and Ophthalmology, Inc.
DOI:  10.1167/iovs.08-1893
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
iovs.08-1893v1
49/10/4284    most recent
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Toit, R. d.
Right arrow Articles by Lamoureux, E. L.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Toit, R. d.
Right arrow Articles by Lamoureux, E. L.

Development and Validation of a Vision-Specific Quality-of-Life Questionnaire for Timor-Leste

Rènée du Toit,1,2,3 Anna Palagyi,1,2,3 Jacqueline Ramke,1,2,3 Garry Brian,1 and Ecosse L. Lamoureux3,4,5

1From The Fred Hollows Foundation (New Zealand), Auckland, New Zealand; 2The International Centre for Eyecare Education, Sydney, Australia; 3The Vision Cooperative Research Centre, Sydney, Australia; the 4Centre for Eye Research Australia, University of Melbourne, East Melbourne, Australia; and the 5Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.

PURPOSE. To develop and determine the reliability and validity of a vision-specific quality-of-life instrument (TL-VSQOL) designed to assess the impact of distance and near vision impairment in adults living in Timor-Leste.

METHODS. A vision-specific quality-of-life questionnaire was developed, piloted, and administered to 704 Timorese aged ≥40 years during a population-based eye health rapid assessment. Rasch analysis was performed on the data of 457 participants with presenting near vision worse than N8 (78.5%) and/or distance vision worse than 6/18 (69.8%). Unidimensionality, item fit to the model, response category performance, differential item functioning, and targeting of items to participants were assessed.

RESULTS. Initially, the questionnaire lacked fit to the Rasch model. Removal of two items concerning emotional well-being resulted in a fit of the data (overall item–trait interaction: {chi}2 (df) = 81 (51); mean (SD) person and item fit residual values: –0.30 (1.02) and –0.32 (1.46), and good targeting of person ability and item difficulty was evident. Poorer distance and near visual acuities were significantly associated with worse quality-of-life scores (P < 0.001). Person separation reliability was substantial (0.93), indicating that the instrument can discriminate between groups with normal and impaired vision. All 17 items were free of differential item functioning, and there was no evidence of multidimensionality.

CONCLUSIONS. This 17-item TL-VSQOL has high reliability, construct, and criterion validity and effective targeting. It can effectively assess the impact on quality of life of adult Timorese with distance and near vision impairment. The TL-VSQOL could be adapted for use in other low-resource settings.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2008 by the Association for Research in Vision and Ophthalmology