Predicting vocal outcome by means of a vocal endurance test: A 5-year follow-up study in female teachers

Objectives: Investigate whether vocal problems in future professional activities can be predicted by early laryngeal and phoniatric evaluation and whether a vocal endurance test can contribute to this evaluation. Study Design: Five-year follow-up study of 30 female education majors, initially documented with a standard voice assessment and a vocal endurance test. Measurements before and after vocal endurance testing were compared and related to the vocal outcome 5 years after the initial testing. Methods: Voice assessment included perceptual evaluation, airflow measurements, Fo and SPL measurements, voice range profile and laryngeal (stroboscopic) examination. The Standard Tolerance Test, as recommended by the Union of European Phoniatricians, was followed. This data set was completed with a questionnaire concerning the subjects' vocal behavior. This questionnaire was repeated 5 years later. Results: No significant differences were found for ENT scores (laryngostroboscopy) (P = .018). Logistic regression was used to determine a relationship between initial observations and the final outcome. Conclusions: The role of an endurance test as used in this study is negligible for the prediction of vocal outcome. A combination of laryngeal examination, maximum phonation time, and perceptual evaluation, assessed prior to the endurance test, reveals a prediction of the vocal outcome with a specificity of 90% and a sensitivity of 70%.