Validating Patient-Reported Outcome Measures for Adolescents with Inherited Retinal Diseases

Abstract

Purpose : Vision structure and function measures are routinely used to assess patients’ visual health and the stage of inherited retinal diseases (IRDs). Though most IRD are of early onset, there are no patient-reported outcome measures specific to adolescent patients with IRDs to explore the condition’s impact on their lives. Given the pressing need to evaluate benefit of IRD therapeutics on patients’ activities of daily living, this observational study validated patient-reported outcome measure tools developed for adults with IRDs, the Michigan Retinal Degeneration Questionnaire (MRDQ) and Michigan Vision-Related Anxiety Questionnaire (MVAQ), in adolescents with IRDs.

Methods : Adolescent patients diagnosed with IRDs were recruited at the Hospital for Sick Children (University of Toronto) and the Kellogg Eye Center (University of Michigan). The patients were administered the MRDQ, MVAQ, and Patient Health Questionnaire-4 (PHQ-4). Adolescent responses were analyzed for response distribution, measurement precision, known-group validity, and differential item functioning. As a further validation step, comparisons were made to adult data from the original MRDQ and MVAQ studies to ensure consistency in response ranges.

Results : The existing MRDQ and MVAQ content and format could accurately detect the impact of IRD on activities of daily living in adolescents with the condition (n = 91). No floor/ceiling effects were identified, test-retest reliability was established for each of the questionnaires’ domains (r = 0.73–0.86), and no items were excluded after differential item functioning analysis. Domain and trait associations with visual acuity and IRD phenotypes were similar between adolescents and adults.

Conclusions : The MRDQ and MVAQ have shown validity for use in adolescent patients with IRDs. Implementation of these tools in practices and studies will enhance the perspective of IRD on the activities of daily living of affected adolescents.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.