Development and initial validation of the child intermittent Exotropia Questionnaire among child strabismus patients

Abstract

Objectives: To translate the Child Intermittent Exotropia Questionnaire (Child-IXTQ) from English to Chinese and to evaluate its reliability and validity in Chinese childhood strabismus patients. Method: A consecutive sample of 143 child strabismus patients was recruited from the Department of Ophthalmology at a medical center in Southwest China. In addition, 100 visually normal adults and 100 patients with other eye diseases were recruited. The Brislin translation model was followed to develop the Chinese version of Child-IXTQ. Reliability was established using Cronbach's α and test-retest. Validity was established encompassing content validity, construct validity, convergent validity, criterion-related validity and discriminative validity. Results: The correlation coefficients between each item score with the total score ranged from 0.370 to 0.813. Two subscales were extracted by principal component analysis, with a content validity of 0.91. The correlation coefficients between two factor scores with the total score were 0.709 and 0.939. Criterion-related validity was estimated by the correlating the Child-IXTQ with the PedsQL 4.0, and the correlation coefficient was 0.522. In addition, the Child-IXTQ discriminated accurately between strabismus patients and normal children, or children with other eye diseases that possessed good discriminative validity. Cronbach's α coefficient for the internal consistency was 0.907 and the test-retest reliability was 0.962. Conclusions: Our study indicates that the Child-IXTQ is a reliable and valid instrument for assessing the health-related quality of life among children with strabismus.

Keywords

• Child strabismus
• Quality of life
• Questionnaire
• Reliability
• Validity