Development of Ocular Surface Disease Specific Item Banks to Measure Quality-of-Life Parameters

Ocular surface diseases (OSDs) are among the most common reasons for patients to visit eye clinics. OSDs encompass a range of conditions that significantly affect quality of life (QoL). The prevalence of OSD is rising and with the lifestyle more reliant on a digital environment, the impact of OSD only seem to have exacerbated. The overarching aim of this doctoral research was to develop a scientifically robust, patient centred, and technologically advanced patient reported outcome measure (PROM) in the form of item banks, designed for administration via a computer adaptive testing (CAT) platform to assess QoL impacts of OSDs. Phase I of this study involved content identification through a systematic review of 34 existing OSD-specific PROMs and a qualitative study with participants from Australia and United Kingdom. The systematic review revealed that while some instruments demonstrated strengths, none comprehensively measured QoL across the full spectrum of OSD and all had psychometric limitations. The content of the PROMs from this review was extracted for item banking. The OSDs included in the qualitative study were dry eye disease (DED), meibomian gland dysfunction (MGD), contact lens discomfort (CLD), anterior blepharitis, ocular surface conditions associated with autoimmune diseases including Sjögren disease, rheumatoid arthritis and thyroid eye disease (TED), and neuropathic corneal pain (NCP). Sixty-two in-depth interviews were conducted with participants across the disease spectrum. A template analysis of these interviews highlighted the substantial impacts of OSDs posed by the variety of symptoms, health concerns, difficulties performing daily activities, inconveniences, emotional wellbeing, social engagement and financial impacts. All concepts elicited through this study supplemented the content elicited from the systematic review to yield 1543 items. Refinement of content consisted of a multi-step systematic process of binning, winnowing and cognitive interviewing through a panel of experts resulting in 653 items across 13 item banks. Phase II involved online administration of these item banks to participants with different types of OSDs, followed by Rasch analysis for psychometric validation and calibration. Preliminary results from 173 participants indicate promising psychometric properties of unidimensionality, measurement precision and fit statistics across 13 item banks. The symptoms domains include 3 rating scales of symptoms frequency, severity and bother. Although further targeted recruitment and calibration are required, these item banks provide a strong foundation for CAT implementation, enabling adaptive item administration, efficient and precise QoL assessment across OSD types. These item banks have potential to transform routine clinical care, research and policy by enabling relevant tools that are more precise and efficient for patient centred measurement of QoL impacts.