The Quix Test: Identifying Vestibular Dysfunction in the "Dizzy Patient"
Kayla Schusterman1, Jeremy Kuder1, Amanda Walker2, Julianne Lee2, Isabella Canut2, Anthony Thompson1, Charles Maitland1, Philippe Gaillard2, Farnaz Solatikia2
1Florida State University College of Medicine, 2Florida State University
Objective:

Our objective was to validate the sensitivity and specificity of the Quix test in the identification of peripheral vestibular dysfunction in the "dizzy" patient and compare it to other conventional tests performed in the routine practice of the evaluation of "dizziness." 

Background:

The complaint of dizziness has ominous implications lending itself to accidental death and increased morbidity and mortality. The evaluation of a dizzy patient can be confounding due to its myriad of potential etiologies, many of which are present comorbidly. Acute peripheral vestibulopathy is a common cause of dizziness. Current conventional tests for vestibular dysfunction offer maximum sensitivity ranging from 50-75% (Cohen, 2019). We developed a modified version of the Quix test in an effort to increase sensitivity.

Design/Methods:

158 patients were evaluated at a balance disorders clinic. Each patient underwent a comprehensive neurological examination and six assessments that detect vestibular dysfunction: a nystagmus test, a head impulse test, a Romberg test, a Quix test, a tandem stance/walk, and a sitting past-pointing test. Posturography, Dix-Hallpike maneuver, and videonystagmography were performed. Results were analyzed to determine the sensitivity of the vestibular tests in detecting dysfunction. 

Results:

The association between the Quix test and vestibular dysfunction was assessed with a chi-square test. The model was statistically significant, χ2 = 4.3175 and p = 0.0377 < .05 = α. The sensitivity was 85.7%, and the specificity was 33.3%. Although specificity was low, a number of patients were found to have benign positional vertigo on clinical examination by a balance therapist. Other conventional tests were not statistically significant predictor variables of vestibular abnormality. 

Conclusions:

A positive Quix test helps identify vestibular dysfunction in the “dizzy patient.” It is cost-effective, time-efficient, and easily administered with minimal training. The Quix test is more sensitive than other conventional tests and can serve as a critical screening tool.

10.1212/WNL.0000000000202635