Measuring vocal function in professional music theater singers: construct validation of the Evaluation of the Ability to Sing Easily (EASE).

OVERVIEW: Working music theater singers (MTS) typically have a heavy vocal load and little is known about their perception of vocal function. The Evaluation of the Ability to Sing Easily (EASE) was used to assess professional MTS' perceptions of current singing voice status and to compare scores across demographic and performance characteristics and to evaluate the construct validity of the EASE and its subscales (VF = Vocal Fatigue, PRI = Pathologic-Risk Indicators). METHODS: Professional MTS (n = 284) completed an online survey including the EASE and two additional Vocal Concern (VC) items. Scores were compared across age, gender, whether currently working, role, perceived vocal load over the past 24 h and self-reported voice problem. RESULTS: For the whole cohort, statistically significant differences were found on all subscales according to whether or not singers perceived themselves to have a voice problem (p < 0.001). Currently performing singers were significantly different from those not performing in a show on the EASE Total (p = 0.014) and VF (p = 0.002), but not for PRI and VC. In the currently performing singer group, significant differences were found for gender, role and perceived voice problem on the EASE Total and all subscales (p < 0.01). Significantly higher VF scores were recorded for singers with heavy vocal load (p = 0.01), but there were no differences on the EASE Total (p = 0.57), PRI (p = 0.19) or VC subscales (p = 0.53). Among these performing singers, no significant age differences were found for any EASE subscales. CONCLUSIONS: These findings provide further validation of the EASE as a useful tool for measuring singers' perceptions of vocal function and suggest that the subscales should be scored separately. Future evaluation of the EASE against objective clinical assessments (e.g., videostroboscopy) is recommended.