Effect of Clinical Expertise on Efficacy of Vocal Function Exercises in Individuals With Typical Voice.

OBJECTIVES/HYPOTHESIS: To determine the effect of clinical expertise on efficacy of Vocal Function Exercises (VFEs) as measured by change in percent of maximum phonation time goal attained. The hypothesis was that clinical expertise would result in greater increases in percent of maximum phonation time goal attained. STUDY DESIGN: Randomized controlled trial. METHODS: A convenience sample of 19 individuals with typical voice was recruited in a university academic clinic setting. All participants completed baseline assessment and 17 completed all study procedures. Participants were randomized to receive VFEs from an expert voice clinician with more than 40 years' experience (expert group (EG)) or from a master's student in Communication Sciences and Disorders trained in VFEs (novice group (NG)). The primary outcome measure was change in percent of maximum phonation time goal attained during VFE tasks 1 and 4. RESULTS: Mean change scores for maximum phonation time were 27.71 (P = 0.001) and 25.31 (P = 0.003) for EG and NG, respectively. Both groups improved significantly on the primary outcome measure, but the difference between groups was not statistically significant (P = 0.759). A Hedges'-g effect size of -0.14 [-1.10, 0.81] was obtained comparing EG and NG groups, indicating a small negative effect of limited clinical expertise on VFE outcomes in individuals with typical voice. CONCLUSIONS: Speech-language pathologists with varied levels of expertise are capable of efficaciously administering VFEs in individuals with typical voice.

The Effect of Maximum Phonation Time Goal on Efficacy of Vocal Function Exercises.

OBJECTIVES/ HYPOTHESIS: To determine the effect of maximum phonation time goal on efficacy of Vocal Function Exercises (VFEs) as measured by percent of maximum phonation time goal attained. The hypothesis was that provision of a maximum phonation time goal would result in greater increases in percent of maximum phonation time goal attained. STUDY DESIGN: Randomized controlled trial. METHODS: A convenience sample of individuals with normal voice were recruited in a university academic clinic setting. Of 34 participants who volunteered for the study, 28 completed baseline assessment and 19 completed all study procedures. Participants were randomized to complete VFEs with knowledge of their maximum phonation time goal (standard goal, SG), with knowledge of their maximum phonation time goal after three weeks (delayed goal, DG), or without knowledge of their maximum phonation time goal (no goal, NG). The primary outcome measure was percent of maximum phonation time goal obtained during VFE tasks one and four. RESULTS: Mean change scores for maximum phonation time were 32.50 (SG), 34.55 (DG), and 21.02 (NG). Hedges' g effect sizes of -0.10 (-1.19, 0.99) and 0.56 (-0.55, 1.67) were obtained comparing DG and SG groups, and NG and SG groups, respectively. CONCLUSIONS: Absence of maximum phonation time goal attenuates VFE efficacy; maximum phonation time goal is an active ingredient within VFEs.

Vocal Function Exercises With and Without Maximally Sustained Phonation: A Randomized Controlled Trial of Individuals With Normal Voice.

OBJECTIVES: To determine the effect of maximally sustained phonation on efficacy of Vocal Function Exercises as measured by percent of maximum phonation time goal attained. The hypothesis was that maximally sustained phonation would result in greater improvements in percent of maximum phonation time goal attained. STUDY DESIGN: Randomized controlled trial. METHODS: A convenience sample of individuals with normal voice were recruited in a university academic clinic setting. Of 34 participants who volunteered for the study, 31 completed baseline assessment and 23 completed all study procedures. Participants were randomized to complete Vocal Function Exercises (traditional group TG), modified Vocal Function Exercises with reduced requirement for maximally sustained phonation (midpoint group MG), or modified Vocal Function Exercises with removed requirement for maximally sustained phonation (baseline group BG). The primary outcome measure was percent of maximum phonation time goal obtained during Vocal Function Exercises. RESULTS: The MG (p = 0.008) and TG (p = 0.001) groups significantly improved percent of maximum phonation time goal attained after six weeks of exercise, while the BG group (p = 0.0202) did not (ɑ = 0.0125). Difference among groups was not statistically significant (p = 0.67, ɑ = 0.0125). Hedges' g effect sizes of 0.29 (-0.66, 1.25) and 0.51 (-0.57, 1.58) were obtained comparing MG and TG groups, and BG and TG groups, respectively. CONCLUSIONS: Greater requirements for maximally sustained phonation improved efficacy of Vocal Function Exercises in enhancing normal voice as measured by percent of maximum phonation time goal attained. Maximally sustained phonation may be modified to some extent while preserving efficacy of Vocal Function Exercises, however complete elimination of maximally sustained phonation may attenuate improvement. Additional research in a clinical population is warranted.

Vocal function exercises for normal voice: With and without semi-occlusion.

PURPOSE: This study examined the effect of varying degrees of vocal tract (VT) occlusion used during Vocal Function Exercises (VFEs) on attainment of maximum phonation time (MPT) goals in normal voice. Greater VT occlusion was expected to result in increased MPT. The overarching goal was to determine whether the semi-occluded vocal tract (SOVT) posture used during VFEs could be modified while preserving efficacy. METHOD: Twenty-six females ages 18-30 participated in this pre-post longitudinal group study. Participants were randomly assigned to three experimental groups and completed a six-week VFE protocol. The first group performed exercises using the prescribed SOVT posture; the second group used the vowel /o/; group three used the vowel /a/. The primary outcome measure was MPT as performed on the exercise tasks using the assigned vocal tract posture. RESULT: MPT significantly improved in the prescribed SOVT group, but did not significantly improve in the modified /o/ and /a/ groups. CONCLUSION: The SOVT posture used during VFEs is modifiable to a small extent without significantly undermining efficacy. Changes in MPT are less robust with reduced VT occlusion. Research in a clinical population is warranted.

Vocal function exercises for normal voice: The effects of varying dosage.

PURPOSE: This study examined the effect of varying dosage of vocal function exercise (VFE) home practice on attainment of pre-established maximum phonation time (MPT) goals in individuals with normal voice. High dosage VFE practice was expected to result in greatest MPT. The overarching goal of this study was to contribute to a VFE dosage-response curve, potentially including a point of observable toxicity. METHOD: Twenty-eight females ages 18-25 with normal voice participated in this pre-post longitudinal group study. Participants were randomly assigned to one of three experimental groups and completed a six-week VFE protocol with practice twice daily. The low dosage group performed each exercise once, the traditional group twice, and the high dosage group four times. The primary outcome measure was MPT as performed on the fourth VFE using the prescribed semi-occluded vocal tract posture. RESULT: No toxic effects were observed. MPT increased for all participants, with significant improvement for traditional and high dosage groups. CONCLUSION: High dosage VFEs may yield more rapid improvement in MPT, however benefits must be weighed against the risk of increased attrition. Low dosage VFEs insufficiently improved MPT. Further research on dosage is warranted, and should include individuals with disordered voice.