Translation, cross-cultural adaptation and initial validation of the PREP questionnaire into Spanish for assessing quality of life in children wearing spectacles

PURPOSE: To translate, culturally adapt, and validate the original Pediatric Refractive Error Profile (PREP) questionnaire into Spanish, enabling assessment of vision-related quality of life (VR-QoL) in children wearing spectacles. METHODS: The PREP was translated and adapted following a five-step protocol. A sample of 124 Spanish children aged 8-14 years with refractive errors (myopia, hyperopia, and/or astigmatism) and ≥1 year of spectacle use completed the Spanish version. Internal consistency was assessed using Cronbach's alpha; test-retest reliability was evaluated in 18 children using intraclass correlation coefficients (ICC). Validity was examined through item-scale correlations, inter-scale correlations (construct validity), and associations with clinical visual parameters and a Visual Analogue Scale (VAS) measuring subjective experience (concurrent validity). RESULTS: All participants completed the questionnaire without difficulties. Cronbach's alpha ranged from 0.754 to 0.918 across the 10 scales. ICC values ranged from 0.541 to 0.921, indicating moderate to excellent reliability. Item-scale correlations exceeded 0.40, and construct validity was supported by moderate to strong inter-scale associations. Significant correlations were found between visual acuity and the vision-related scales, and between VAS scores and the appearance, satisfaction, and activities scales. Children with visual acuity deficits showed significantly lower scores in several domains. CONCLUSIONS: The Spanish version of the PREP questionnaire shows preliminary evidence of reliability and validity for assessing vision-related quality of life in children wearing spectacles. However, further studies are needed to confirm its psychometric properties using more comprehensive validation approaches.