OBJECTIVES: The aim of this research was to evaluate the content validity of the Dry Eye Disease Questionnaire (DED-Q), a newly-developed patient-reported outcome measure suitable for use in Dry Eye Disease (DED), Meibomian Gland Dysfunction (MGD), and Sjogren’s Syndrome Dry Eye Disease (SS-DED).

METHODS: Cognitive debriefing (CD) of the DED-Q was conducted with a sample of 60 US adults with DED (n=20), MGD (n=20), and SS-DED (n=20). Interviews were conducted over two rounds and employed a ‘think aloud’ approach to evaluate patients’ understanding of the instructions, items, response options, and recall periods, and to obtain feedback on perceived relevance of concepts assessed across various modules. Interviews were also conducted with eight health care professionals to assess clinical relevance of the concepts included.

RESULTS: Participants had a mean age of 50 years (range 21-80 years) and were mostly female (63%). Over 70% of patients demonstrated good understanding of DED-Q items and over 75% of patients confirmed most concepts were relevant to their lived experience of their condition. Following round 1 interviews, the instruction wording was modified for the Symptom and Visual Tasking modules to encourage patients to focus only on dry eye vision problems, and enable better interpretation and accuracy in responses. The Environmental Triggers module was removed from the DED-Q and wording of the Eye Dryness Severity and Eye Dryness Frequency modules was revised to improve overall concept relevance across the patient groups. Modifications were made to the Symptoms module to more clearly discriminate eyeball redness from eyelid redness.

CONCLUSIONS: Findings from the CD interviews confirm the DED-Q as a content valid PRO measure suitable for use in clinical studies to assess the patient experience of DED, MGD, and SS-DED. Future work will focus on evaluating the psychometric properties of the DED-Q for use as efficacy endpoints in clinical trials.