Abstract
Purpose :
The Pediatric Refractive Error Profile 2 (PREP2) is a survey to measure aspects of the vision-related quality of life of children with refractive error. The purpose of this study was to assess the validity of the survey and examine relationships between PREP2 scores and baseline characteristics of children enrolled in the BLINK Study, a randomized clinical trial to examine the effects of multifocal versus single vision soft contact lenses on myopia progression.
Methods :
Subjects completed the survey after wearing their randomly assigned contact lenses for two weeks, and data were analyzed using Rasch analysis to assess measurement precision (person separation statistic), response category functioning, and unidimensionality. Additionally, Rasch analysis was used to estimate interval-level person scores for each scale. The relationships between the scale scores and age, gender, cycloplegic spherical equivalent, and treatment group were analyzed using ANOVA and Spearman correlation.
Results :
289 subjects were enrolled with mean±SD age of 10±1 years (range = 7 to 11). Mean cycloplegic spherical equivalent refractive error OD was −2.38±1.01 D (range = −0.82 to −5.49 D). Response category function and item fit to the Rasch model were good for all scales. There was no evidence of multidimensionality in the measures by principal component analysis of model residuals. Measurement precision, assessed by the Rasch person separation statistic, was less than ideal for most scales. The Symptoms scale performed best, with good person separation and no evidence of multidimensionality. There were gender differences in scores on the Symptoms (P=.006), Appearance (P=.014), and Handling (P=.003) scales. Scores on the Vision subscale differed by treatment assignment (P=.03), with lowest scores for the +2.50D add group. There were low but significant correlations between age and the Appearance (ρ =.16, P=.007), Handling (ρ=.14, P=.02), Peer (ρ=.17, P=.003), and Overall (ρ=.13, P=.032) scales. OD spherical equivalent refractive error was correlated with Peer scale score (ρ=.17, P=.004).
Conclusions :
The PREP2 survey scales showed generally good fit to the Rasch model but could be improved with better measurement precision. Scores on several scales showed relationships with characteristics of myopic children including age, gender, and refractive error. Future studies could examine survey performance in a more heterogeneous sample.
This is a 2021 ARVO Annual Meeting abstract.