Patient Motivation for Voice Therapy Increases After Stimulability Testing: Validation of a Voice Therapy Motivation and Voice Perception Inventory.

Abstract

Measuring patient motivation for voice therapy is an important component of determining prognosis and estimating compliance. Voice stimulability testing is assumed to influence the patient's motivation by improving their perception of the sound and/or feel of the voice. The purpose of this study was to validate a Voice Therapy Motivation and Voice Perception Inventory and to determine whether stimulability testing elicits improvements in motivation and patient-perceived voice status. Seventy-five patients who underwent initial voice therapy evaluation completed a four-item inventory that queried their commitment to voice therapy, confidence that they could change their voice through voice therapy, perception of their voice severity, and ratings of their vocal effort. Inventories were completed shortly before and after stimulability testing. A psychometric analysis of the survey was conducted, including the internal consistency of each construct of the inventory along with content, predictive, and concurrent validity. Paired-samples statistical analyses were conducted to determine differences before and after stimulability testing, and Spearman correlations between voice and motivation ratings were conducted to determine relationships between the patient's perception of their voice and their motivation for voice therapy. Internal consistency reliability was acceptable to good for each construct, particularly after stimulability testing. Motivation scales were predictive of returning for voice therapy sessions, subjective improvement of voice by the first therapy session, and likelihood of the patient practicing the home practice program. Patient ratings of voice severity and effort were positively correlated with clinician ratings of overall severity. Motivation and voice impairment perception improved following stimulability testing. Reduction in vocal effort was related to improved motivation, but change in voice severity was not. Voice stimulability testing can influence patient motivation for voice therapy and patient-perceived voice improvements. It should be considered a critical part of the voice evaluation.