Thesis Defense — VISually Independent Test Battery of NeuroCOGnition (VISION-Cog): A Novel Diagnostic Tool to Assess Cognitive Impairment in Visually Impaired Older Adults

With a rapidly ageing global population, the prevalence of comorbid visual impairment (VI) and cognitive impairment (CI) is expected to increase. Importantly, the co-presence of VI and CI is common, with 1 in every 3 patients diagnosed with CI also having VI. However, current CI diagnostic instruments rely on visually dependent tasks and are therefore not suitable to assess CI in visually impaired older adults. Thus, I proceeded to develop the VISually Independent test battery Of NeuroCOGnition (VISION-Cog), a new diagnostic tool to assess CI in older adults with VI. First, I conducted a systematic review and meta analysis to elucidate the relationship between VI and CI and ascertain the paucity of instruments available to evaluate CI in the visually impaired. Next, I designed a pilot version of the VISION-Cog using iterative stages of literature review and field expert consultation. This pilot version was then fine-tuned through a mixed-method approach of pilot testing and expert consensus. Following this rigorous process, I have developed a feasible, comprehensible, and acceptable VISION-Cog capable of replacing visually dependent test batteries and support the clinician-based diagnosis of CI in older adults with VI.