Association between subjective tinnitus and cognitive performance: protocol for systematic review and meta-analysis

INTRODUCTION: Subjective tinnitus is very common and has a number of comorbid associations including depression, sleep disturbance and concentration difficulties. Concentration difficulties may be observable in people with tinnitus through poorer behavioural performance in tasks thought to measure specific cognitive domains such as attention and memory (ie, cognitive performance). Several reviews have discussed the association between tinnitus and cognition; however, none to date have investigated the association between tinnitus and cognitive performance through meta-analysis with reference to an established theoretical taxonomy. Furthermore, there has been little overlap between sets of studies that have been included in previous reviews, potentially contributing to the typically mixed findings that are reported. METHODS AND ANALYSIS: This systematic review aims to comprehensively review the literature using an established theoretical taxonomy and quantitatively synthesise relevant data to determine associations between subjective tinnitus and cognitive performance. Methods are reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. All study designs will be eligible for inclusion with no date restrictions on searches. Studies eligible for inclusion must contain adult participants (≥18 years) with subjective tinnitus and a behavioural measure of cognitive performance. Meta-analysis will be reported via correlation for the association between tinnitus and cognitive performance. ETHICS AND DISSEMINATION: No ethical issues are foreseen. Findings will be reported in a student thesis, at national and international, ear, nose and throat/audiology conferences and by peer-reviewed publication. PROSPERO REGISTRATION NUMBER: CRD42018085528.