Development of the 25-item Cardiff visual ability questionnaire for children (CVAQC)

Khadka, J., Ryan, B., Margrain, T.H., Court, H. and Woodhouse, J.M. (2010) Development of the 25-item Cardiff visual ability questionnaire for children (CVAQC). British Journal of Ophthalmology, 94(6), pp. 730-735. (doi: 10.1136/bjo.2009.171181)

Abstract

<br>Aims To develop and validate a short questionnaire to assess self-reported visual ability in children and young people with a visual impairment.</br> <br>Methods A list of 121 items was generated from 13 focus groups with children and young people with and without a visual impairment. A long 89-item questionnaire was piloted with 45 visually impaired children and young people using face-to-face interviews. Rasch analysis was used to analyse the response category function and to facilitate item removal ensuring a valid unidimensional scale. The validity and reliability of the short questionnaire were assessed on a group of 109 visually impaired children (58.7% boys; median age 13 years) using Rasch analysis and intraclass correlation coefficient (ICC).</br> <br>Results The final 25-item questionnaire has good validity and reliability as demonstrated by a person separation index of 2.28 and reliability coefficient of 0.84. The items are well targeted to the subjects with a mean difference of −0.40 logit between item and person means, and an ICC of 0.89 demonstrates good temporal stability.</br> <br>Conclusion The Cardiff Visual Ability Questionnaire for Children (CVAQC) is a short, psychometrically robust and a self-reported instrument that works to form a unidimensional scale for the assessment of the visual ability in children and young people with a visual impairment.</br>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Court, Dr Helen
• Authors: Khadka, J., Ryan, B., Margrain, T.H., Court, H., and Woodhouse, J.M.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Mental Health and Wellbeing
• Journal Name: British Journal of Ophthalmology
• ISSN: 0007-1161
• ISSN (Online): 1468-2079