Validity and Responsiveness of the Visual Vertigo Analogue Scale

People with visual vertigo have dizziness provoked by visual stimulation. We have developed a Visual Vertigo Analogue Scale (VVAS) to evaluate their symptoms and response to rehabilitation. Our goal was to validate the VVAS against the Situation Characteristics Questionnaire (SITQ) score and determine its responsiveness to treatment.

Participants (n = 115) completed 3 questionnaires: Dizziness Handicap Inventory (DHI), VVAS, and the SITQ at their initial and final sessions of vestibular rehabilitation. The SITQ was analyzed using the Space Motion Discomfort (SMD1) outcome measure and by calculating the average score of all the items (SMDavg). The results were stratified into those who had a significant clinical change in their DHI score posttreatment and those who did not. Associations of the VVAS with SMD scores and change scores were determined by Pearson and Spearman correlations. Nonparametric t tests were used to compare the 2 DHI groups on the clinical outcomes.

There were significant associations between VVAS scores (P < 0.0001) and both SMD1 (βVVAS = 0.02) and SMDavg scores (βVVAS = 0.03). Significant differences existed between the 2 DHI groups for all scores: VVAS (P = 0.0002), SMD1 (P = 0.02), and SMDavg (P = 0.0001).

VVAS scores correlated well with SMD1 and SMDavg scores. Changes in VVAS pre- and posttreatment scores corresponded to the changes seen in SMD1 and SMDavg scores. The VVAS shows validity and responsiveness to change. The VVAS can be used to detect clients with visual vertigo and to verify the progression of the client's symptoms.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A258).