RT Journal Article
SR Electronic
T1 Validation of an instrument to assess visual ability in children with visual impairment in China
JF British Journal of Ophthalmology
JO Br J Ophthalmol
FD BMJ Publishing Group Ltd.
SP 475
OP 480
DO 10.1136/bjophthalmol-2016-308866
VO 101
IS 4
A1 Jinhai Huang
A1 Jyoti Khadka
A1 Rongrong Gao
A1 Sifang Zhang
A1 Wenpeng Dong
A1 Fangjun Bao
A1 Haisi Chen
A1 Qinmei Wang
A1 Hao Chen
A1 Konrad Pesudovs
YR 2017
UL http://bjo.bmj.com/content/101/4/475.abstract
AB Objective To validate a visual ability instrument for school-aged children with visual impairment in China by translating, culturally adopting and Rasch scaling the Cardiff Visual Ability Questionnaire for Children (CVAQC).Methods The 25-item CVAQC was translated into Mandarin using a standard protocol. The translated version (CVAQC-CN) was subjected to cognitive testing to ensure a proper cultural adaptation of its content. Then, the CVAQC-CN was interviewer-administered to 114 school-aged children and young people with visual impairment. Rasch analysis was carried out to assess its psychometric properties. The correlation between the CVAQC-CN visual ability scores and clinical measure of vision (visual acuity; VA and contrast sensitivity, CS) were assessed using Spearman's r.Results Based on cultural adaptation exercise, cognitive testing, missing data and Rasch metrics-based iterative item removal, three items were removed from the original 25. The 22-item CVAQC-CN demonstrated excellent measurement precision (person separation index, 3.08), content validity (item separation, 10.09) and item reliability (0.99). Moreover, the CVAQC-CN was unidimensional and had no item bias. The person–item map indicated good targeting of item difficulty to person ability. The CVAQC-CN had moderate correlations between CS (−0.53, p<0.00001) and VA (0.726, p<0.00001), respectively, indicating its validity.Conclusions The 22-item CVAQC-CN is a psychometrically robust and valid instrument to measure visual ability in children with visual impairment in China. The instrument can be used as a clinical and research outcome measure to assess the change in visual ability after low vision rehabilitation intervention.