Psychometric validation of the Chronic Ocular Pain Questionnaire (COP-Q).

Background: The Chronic Ocular Pain Questionnaire (COP-Q) is a newly developed patient-reported outcome (PRO) measure intended to assess symptoms and impacts associated with Chronic Ocular Surface Pain (COSP). This study assessed the psychometric properties of the COP-Q to determine the adequacy of the COP-Q as a 'fit-for-purpose' instrument to derive trial endpoints for future clinical studies in COSP.

Methods: Patients with COSP completed the COP-Q daily for four weeks on an electronic, touch-screen, tablet device as part of a longitudinal, observational study in the United States (N = 124).