Identification and Evaluation of Items for Vitreoretinal Diseases Quality of Life Item Banks

ABSTRACT

Purpose: We are developing item banks assessing the impact of retinal and vitreoretinal diseases (excluding age-related macular degeneration, diabetic retinopathy, and retinal detachment, covered elsewhere) on quality of life (QoL) for adults. This study outlines the first two phases of the multi-stage process: content development and item evaluation.

Methods: We grouped retinal and vitreoretinal diseases into hereditary and acquired. Development of the item banks involved two phases: item identification and item evaluation. The items were extracted from three sources: (1) 17 pre-existing PRO instruments, (2) 4 qualitative studies and (3) 79 semi-structured interviews. Item evaluation involved three stages namely, binning (grouping) and winnowing (reduction), expert panel opinion and cognitive interviews.

Results: The item identification phase yielded 1,217 items. After three sessions of binning and winnowing, items were reduced to a minimally representative set (n = 411) across nine QoL domains namely, activity limitation, emotional, social, health concerns, symptoms, economic, mobility, convenience, and coping. The hereditary group had a total of 345 items and the acquired group had a total of 257 items. After 23 cognitive interviews items were amended for hereditary diseases resulting in a final set of 345 items and 3 items were amended for acquired diseases, resulting in a final set of 254 items. Overall across nine domains 189 items were common to hereditary and acquired retinal and vitreoretinal diseases.

Conclusion: As most of the items were unique to hereditary versus acquired retinal and vitreoretinal disease groups separate item banks are required to capture the QoL impacts for hereditary and acquired retinal and vitreoretinal diseases.

KEYWORDS:

• Retinal disease
• retina
• vitreoretinal diseases
• hereditary
• patient-reported outcome instruments
• quality of life
• item banks
• computerised adaptive testing

Acknowledgments

We would like to thank all the members of The Royal Society for the Blind, Adelaide and Retina Australia (South Australia, Western Australia, Queensland, New South Wales and Victoria) for participating in this research. We would also like to thank the staff of Flinders Vision for helping us with patient recruitment. We would also like to thank our research assistant Ms Susan Aldhous.

Conflict of interest

The authors report no conflicts of interest and have no proprietary interest in any of the materials mentioned in this article.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This study is funded by National Health and Medical Research Council (grant no. 1031838). Mallika Prem Senthil is supported by the Australian Government Research Training Scholarship program.