LAUSR

PURPOSE Construct and validate a patient-reported outcome measure for screening and monitoring vision-related anxiety in patients with inherited retinal degenerations. DESIGN Item-response theory and graded response modeling to quantitatively validate questionnaire items generated from qualitative interviews and patient feedback. METHODS Patients at the Kellogg Eye Center (University of Michigan) with a clinical diagnosis of an inherited retinal degeneration (n=128) participated in an interviewer-administered questionnaire. The questionnaire consisted of 166 items, 26 of which pertained to concepts of "worry" and "anxiety". The subset of vision-related anxiety questions was analyzed by a graded response model using Cai's Metropolis-Hastings Robbins-Monro algorithm R (version 3.6.3) mirt package. Item reduction was performed on the basis of item fit, item information, and item discriminability. To assess test-retest variability, 25 participants completed the questionnaire a second time 4-16 days later. RESULTS The final questionnaire consisted of 14-items divided into two unidimensional domains: rod-function and cone-function anxiety. The questionnaire exhibited convergent validity with the Patient Health Questionnaire (PHQ-4) for symptoms of depression and anxiety. This vision-related anxiety questionnaire has high marginal reliability (0.81, 0.83) and exhibits minimal test-retest variability (ρ=0.81 (0.64, 0.91); 0.83 (0.68, 0.92)). CONCLUSIONS The Michigan Vision-related Anxiety Questionnaire (MVAQ) is a psychometrically validated 14-item patient-reported outcome measure to be used as a psychosocial screening and monitoring tool for patients with inherited retinal degenerations. It can be utilized in therapeutic clinical trials for measuring the benefit of an investigational therapy on a patient's vision related anxiety.