Vocal Tract Discomfort Scale: Validation of the Argentine Version

Abstract

The objective of this study was to validate the Vocal Tract Discomfort Scale (VTD) Argentine version. Nonrandomized, cross-sectional prospective study with control group. The VTD Scale was culturally and linguistically adapted to Argentinian Spanish according to the recommended requirements of translation, closely observing the methodology that was suggested (translation, summary, review and back-translation). The scale Argentine version (Escala de disconfort del tracto vocal) was administered to 107 patients with muscle-tension dysphonia (MTD) (23 men and 84 women, mean ages being: 32.30 ± 9.09 years old for MTD type I, and 31.23 ± 8.45 years old for MTD type II) and 30 volunteers with no vocal pathology (9 men and 21 women, mean ages being: 44.3 ± 8.72 years old). All patients completed the Escala de disconfort del tracto vocal before and after Mathieson Laryngeal Manual Therapy. The results of the VTD Scale administered in both patients and vocally healthy subjects were initially compared; the changes arising from pre and post therapy were also compared in the second phase. The internal consistency of the VTD Scale was assessed using Cronbach alpha coefficient. The internal consistency assessed was considered acceptable for both subscales within the VTD Scale. The values obtained for frequency, severity, and total score of the Scale were similar in patients with MTD I and MTD II, marking a difference with those obtained in the control group of healthy volunteers. A lump feeling in the throat was one of the most frequent symptoms in both MTD and vocally healthy groups. The VTD Scale shows an acceptable consistency, so it is a highly reproducible, reliable, and valuable instrument of evaluation to assess Argentinian patients with voice disorders.