Vocal hygiene education, voice production therapy, and the role of patient adherence: a treatment effectiveness study in women with phonotrauma.

PURPOSE: To assess the effectiveness of vocal hygiene education (VHE) and voice production therapy (VP) in altering patient perception of vocal handicap in adult women with benign, bilateral phonotraumatic vocal fold lesions and the role of adherence in that perception. METHOD: Sixty-two women were randomly assigned to 6 weeks of VP (n = 31) or VHE (n = 31), followed by 4 weeks of self-study. The primary outcome measure was the Voice Handicap Index (VHI) score, assessed at baseline, post-therapy, and post-self-study. Patient adherence was assessed as a cofactor. RESULTS: Both groups achieved a decrease in VHI scores from baseline to completion of the study, although the improvement was significantly greater for the VP group. The treatment effect size was large for the VP group and small for the VHE group. More participants adhered to VP than to VHE. Only adherent participants achieved significant improvement. Only adherent participants in the VP group improved with self-study. More than two thirds of the VP group achieved final VHI scores within normal limits, compared with approximately one third of those in the VHE group. CONCLUSIONS: VP therapy may be more effective than VHE in addressing patient perception of vocal handicap in adult women with phonotrauma, and self-study may be an important component of therapy. However, adherence is a critical mediator of outcome.