Validation of the OMNI vocal effort scale in the treatment of adductor spasmodic dysphonia.

[OBJECTIVES] To establish the validity of the OMNI Vocal Effort Scale (OMNI-VES) for resistance exercise, a single-question pictorial scale, in voice-related perceived exertion. Additionally, the study aimed to assess the role of the OMNI-VES as an outcome measurement in the treatment of adductor spasmodic dysphonia (ADSD).

[METHODS] A prospective validation study was conducted on 226 participants. The case group was comprised of 178 patients receiving botulinum toxin (BTX) injections for ADSD and 48 controls without a voice disorder. Prior to a planned injection, the participants were asked to complete the OMNI-VES and the Voice-Related Quality-of-Life (V-RQOL) questionnaires, and the clinician completed the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V). A subgroup of 17 patients were administered a repeat assessment 1 month after injection.

[RESULTS] There was a weak correlation between the OMNI-VES and the V-RQOL score (Tau-b = -0.252, P < 0.001), and no significant correlation with the CAPE-V. Participants with ADSD had significantly higher OMNI-VES scores compared with normal controls, 5.07 ± 2.18 and 1.47 ± 2.28, respectively (P value < 0.0001). The average OMNI-VES score significantly improved 1 month following a BTX injection, from 6 ± 2.4 to 3.4 ± 2.8 (P value = 0.0003). Eighty-eight percent of the patients demonstrated a decrease in the OMNI-VES score following injection, whereas only 47% demonstrated an improvement in the V-RQOL score.

[CONCLUSION] The OMNI-VES is a validated tool for rating perceived voice-related exertion in people with ADSD and can be used for evaluating response to BTX injection treatment.

[LEVEL OF EVIDENCE] 2b Laryngoscope, 129:448-453, 2019.