Psychometric Properties of the Keratoconus Outcomes Research Questionnaire: A Save Sight Keratoconus Registry Study
Himal Kandel, Konrad Pesudovs, Alex Ferdi, Richard Mills, Jern Yee Chen, Adam Watson, Alexander Poon, Laura E Downie, Stephanie L Watson
Cornea | LIPPINCOTT WILLIAMS & WILKINS | Published : 2020
PURPOSE: The aim of this study was to evaluate the psychometric properties of the Keratoconus Outcomes Research Questionnaire (KORQ) in patients enrolled in the Save Sight Keratoconus Registry. METHODS: A cross-sectional study was conducted utilizing prospectively collected web-based registry data. The psychometric properties of the KORQ were assessed using both classical test theory and Rasch analysis. Andrich group rating scale variant of the Rasch analysis was conducted using Winsteps software, Version 3.92.1. RESULTS: The KORQ was completed by 189 patients with keratoconus (men, 67.7%; white, 69.8%; median age 29 years; better eye median values: visual acuity, 75 LogMAR letters; Kmax, 51..View full abstract
The Save Sight Keratoconus Registry was supported by grants from the Ophthalmic Research Institution of Australia, Keratoconus Australia, and the Claffy Foundation. H. Kandel is a Kornhauser Research Associate supported by a philanthropic donation from Larry Kornhauser. A. Ferdi is supported by a Northcote Scholarship. S. Watson is supported by the Sydney Medical School Foundation.