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

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.

Randomized controlled trial.

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.

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.

Absence of maximum phonation time goal attenuates VFE efficacy; maximum phonation time goal is an active ingredient within VFEs.