Rasch Analysis of the Student Refractive Error and Eyeglass Questionnaire-R in Myopic School-Aged Children/Children and Young People in London

Abstract

BACKGROUND: Multiple vision-related quality of life (VRQoL) instruments exist, but questionnaires designed specifically for myopic children that are appropriate for assessing the impact of refractive error are rare. The aim of the study is to assess SREEQ-R validity and to determine if this instrument is appropriate to measure VRQoL related to spectacle utilization in school-aged children sample with myopia in London. METHODS: This study, which utilized prospective questionnaire methodology, was conducted in London. Children up to the age of 18 years who presented for an eye examination with current or previous reported use of eyeglasses and who met the study requirements for spectacle prescription were included. SREEQ consists of 20 specific items divided into two parts with 3 response categories. WithoutGlasses relates to perceptions of uncorrected vision/not wearing glasses and WithGlasses relates to perceptions of corrected vision/wearing glasses followed by demographic and clinician details. Rasch analysis was used to explore the psychometric performance of the questionnaire and scale using WINSTEPS software. Results: A total of 125 eligible children completed the SREEQ-R, with mean age of 12.7±2.9. All items fit the Rasch model and were retained and the scale was unidimensional (as indicated by principal-components analysis of the residuals). All children and item Infit and Outfit MNSQs fell within recommended fit criteria. Without Glasses the item that students were bothered least by was “feeling dizzy” and in contrast the item that affected respondents most was “problems seeing the board, at the movies or other things far away”. While With Glasses, students found the same item “feeling dizzy” to be the least bothering item and “I get headache, or my head or eyes hurt when I read” to be the most problematic symptom. As per the Rasch analysis, person reliability coefficient for the Without Glasses version was 0.84 and 0.91 for the With Glasses version. The item reliability for Without Glasses version was 0.99 and 0.80 for the With Glasses version. Conclusions: The SREEQ-R had satisfactory psychometric properties and Rasch analysis further supported the construct validity of the scale to measure the impact of uncorrected and corrected refractive error on VRQoL in myopic school-aged children in London. The SREEQ-R could be used in future studies to evaluate improvement in VRQoL.