Cambridge Neuropsychological Test Automated Battery is a semiautomated computer program that utilizes a touch screen technology and press pad, to assess neurocognitive function. The Cambridge Neuropsychological Test Automated Battery core cognition battery is a validated cognitive assessment system for assessing multiple components of cognitive function, including attention, visual memory, spatial memory, executive function and reaction time.

The Montreal Cognitive Assessment Tool is a rapid screening tool for mild cognitive dysfunction. It assesses different cognitive domains: attention and concentration, executive function, memory, language, visuoconstructional skills, conceptual thinking, calculations, and orientation. The scores range from 0-30. Higher scores indicate better outcomes while lower scores are indicative of poorer outcomes. It has been recommended that a cut-off scores of 23/30 be used to identify multi-domain cognitive impairment.

The Speech in Babble Test is a low redundancy speech in babble type noise test. The Speech in Babble Test is presented on a calibrated computer using Matlab software. There are 8 in total phonemically and phonetically balanced word lists. The words are presented in the background of a 20-talker babble noise. Two randomly selected monosyllabic consonant vowel consonant word lists in a background of multitalker babble are presented to each ear (i.e. each ear is tested twice). The signal to noise ratio during the test is varied adaptively.

Standard pure tone audiometry is considered a 'gold' standard test of audiologic examination. This test will be completed with a portable calibrated audiometer (GSI Pello Standard model with DD45's, IP30 and B81, Serial Number: GS0071085, calibrated by Guymark UK Ltd).

Participants' physical activity level will be assessed using a wrist-worn accelerometer, the Axivity Wrist Band 3-Axis logging accelerometer. The Axivity Wrist Band 3-Axis logging accelerometer captures triaxial acceleration data at 100 Hz with a dynamic range of ±8 g and has been widely used in population-based studies to assess physical activity levels.

The Activity-specific Balance Confidence Scale is a self-perceived questionnaire with 16 items and assesses balance confidence in daily activities. Scores range from 0 to 100. Higher scores are indicative of better outcome while lower scores indicate poorer outcome. A score ≤67/100 indicate increased falls risk.

The Hospital Anxiety and Depression Scale, a 14-item scale which assesses non-somatic anxiety and depression symptoms, will also be completed. Scores range from 0 to 21 for each subscale with a score ≥8 proposed for the identification of caseness, for both depression and anxiety. Higher scores are indicative of poorer outcomes.

The Pittsburgh Sleep Quality Index generates seven component scores: subjective sleep quality, sleep latency, sleep duration habitual sleep efficiency, sleep disturbance, use of sleeping medication, and daytime dysfunction. The sleep component scores are summed to yield a total score ranging from 0 to 21 with the higher total score (referred to as global score) indicating worse sleep quality while lower scores indicate better outcomes. In distinguishing good and poor sleepers, a global Pittsburgh Sleep Quality Index score >5 yields a sensitivity of 89.6% and a specificity of 86.5%.

The Epworth Sleepiness Scale is a validated and widely used questionnaire exploring daytime sleepiness. It consists of eight questions that are added together to obtain a single number. Higher scores indicate sleeping disorder while lower scores are indicative of better outcomes. Scores range from 0 to 24. The reference range of 'normal' Epworth Sleepiness Scale scores is 0-10 while Epworth Sleepiness Scale scores of 11-24 represent increasing levels of 'excessive daytime sleepiness'.

The EQ-5D-5L is a generic measure of health status for clinical and economic appraisal. The EQ-5D-5L descriptive system comprises of 5 dimensions (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression). Each dimension has 5 levels: no problems, slight problems, moderate problems, severe problems, and extreme problems.

The VSS is used to assess the frequency and severity of common vestibular (Vertigo Symptom Scale-V; e.g. vertigo, imbalance) and autonomic/somatic (Vertigo Symptom Scale-A; e.g. heart pounding, heavy feeling in the arms or legs) symptoms. Scores range from 0 to 60. Normalised scores range from 0-4, with higher scores indicating a higher (i.e. worse) level of symptoms while lower scores indicate better outcomes.

The Situational Vertigo Questionnaire -shortened version measures how frequently symptoms are provoked or exacerbated in environments with visual vestibular mismatch or intense visual motion (e.g. travelling on escalators, crowds, scrolling computer screens). Scores range from 0 to 4. Higher scores indicate poorer outcomes while lower scores are indicative of better outcomes. Scores ≥0.7/4 indicate visual induced dizziness symptoms.

The Dizziness Handicap Inventory is a 25-item self-assessment inventory designed to evaluate self-perceived handicap imposed by symptoms of dizziness. It consists of three domains: emotional, functional and physical. Total scores range from 0 to 100, with higher score indicating greater perceived handicap while lower scores are indicative of better performance. Scores between 0-30, 31-60, and 61-100 on the Dizziness Handicap Inventory indicate mild, moderate, and severe perceived handicap respectively, and can differentiate a person's functional abilities.

The Cognitive and Behavioural Symptom Questionnaire is a measure of subjects' cognitive (i.e. beliefs) and behavioural responses to symptoms of their health condition. This measure includes five cognitive (i.e. beliefs) subscales: Symptom Focusing, Catastrophizing, Damaging Beliefs, Fear Avoidance and Embarrassment Avoidance; and two behavioural subscales: All or- Nothing and Avoidance/Rest.

The Illness Perception Questionnaire-Revised was used to measure participants' illness perceptions. The Illness Perception Questionnaire-Revised measures the key components in Leventhal's common sense self-regulatory model: Illness identity will measured by asking patients to indicate whether they have experienced and attribute a number of potential symptoms to their dizziness condition. Scores range from 0 to 24 with higher scores indicating increased illness identity while lower scores indicate better outcomes.