TY - JOUR T1 - Development of the 25-item Cardiff Visual Ability Questionnaire for Children (CVAQC) JF - British Journal of Ophthalmology JO - Br J Ophthalmol SP - 730 LP - 735 DO - 10.1136/bjo.2009.171181 VL - 94 IS - 6 AU - Jyoti Khadka AU - Barbara Ryan AU - Tom H Margrain AU - Helen Court AU - J Margaret Woodhouse Y1 - 2010/06/01 UR - http://bjo.bmj.com/content/94/6/730.abstract N2 - Aims To develop and validate a short questionnaire to assess self-reported visual ability in children and young people with a visual impairment.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).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.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. ER -