Responsiveness of Vocal Tract Discomfort Scale

Background and Objectives. The self- assessment questionnaire as VTD provides useful clinical information about vocal tract symptoms of voice disorder that experienced by patients The VTD scale assess frequency and severity of eight qualitative descriptors of discomfort that indicated by patients with voice disorders. Burning, tight, dry, aching, tickling, sore, irritable, and the lump are the physical sensations of VTD scale that evaluate by patients with voice disorders. The voice assessment scales like any other scales should be reliable and valid as well as responsive to change. Responsiveness is an important concept inmethodological study of tests and scales. Based on the definitions, it is a capacity of a scale to detect change in client situation. This study was aimed at determining the effectiveness ofvoice therapy in vocal mass lesionswith secondary MTD.Materials and Methods. Thirty patients with vocal fold nodules, polyps and cysts related to secondary MTD participated in the study. To evaluate responsiveness to voice therapy, the measures of interest and videostroboscopy examination were used before and after the sixteen sessions of the voice therapy. For internal responsiveness, Size of Standard Effect and MSR was performed and Pearson coefficient for external responsiveness. Furthermore, the ROC curve analysis was used to separate those improved (moderately or greatly improved) and stable ( slightly improved) patients.Findings.The findings indicatedhigh internal responsiveness for the total score and subscales of VTD (0.8˂). There was poor correlation coefficient between the videostroboscopy(external standard) and the VTD scale (r Pearson = -0.2-0.3). The ROC analysis indicated that the target voice assessment scale did not significantly separate those improved and stable subjects (AUC=0)Conclusion. This study recommends the VTD scale to show voice therapy changes for clinical and research purposes. The target voice scale changes were not able to predict that the videstroboscopy changes as external standard. Furthermore, we recommend that the VTD scale may not properly classify those improved and stable patients.

Keywords:

Vocal Tract Discomfort , vocal mass lesions , Muscle Tension Dysphonia