Constructing country-specific quality-of-life item banks for adults with amblyopia and strabismus in Australia and India

Abstract

ABSTRACT Clinical relevance Understanding the quality-of-life (QoL) impacts of amblyopia and strabismus from the perspectives of patients using validated tools would enable eye care practitioners to provide better clinical management. Background Item banks are advanced patient reported outcome measures with several advantages over traditional QoL assessment. This paper describes the development of amblyopia and strabismus-specific QoL item banks for two distinct country settings: Australia (high-income) and India (low-middle income) and examines the unique QoL issues. Methods Using a bottom-up systematic approach, the content for the item banks was identified from three sources: existing self-report amblyopia and strabismus questionnaires (n = 22), qualitative literature (n = 5) and prospective qualitative studies in Australia (n = 49) and India (n = 30). The initial item pool underwent item evaluation, construction, and pre-testing to form optimal sets of representative items. The Indian item pools were first developed in English and translated into Hindi and Tamil using a rigorous translation protocol. The differences in QoL experiences that emanated from the qualitative studies and the number of common and unique items in the final item pools were compared. Results The final Australian and Indian item pools comprised 312 and 277 items, respectively, covering 11 QoL domains. Two hundred and sixty items (79%) were common to both countries, and 21% were unique. Of the 11 domains, except for activity limitation (64.5%), visual symptoms (73.3%) and emotional impact (75.5%) domains, all other domains had over 80% of items common to both countries. The unique items can be attributed to differences in QoL experiences, individual perspectives, culture, lifestyle, country setting and health systems. Conclusion Amblyopia has a multifaceted impact on QoL irrespective of the country settings. Despite a huge overlap in QoL impacts between Australia and India, both countries had unique issues, especially activity limitations. The study developed comprehensive, country-specific item pools for Australia and India.