PURPOSE: The aim of this work is to verify the efficacy of direct and indirect vocal interventions in preventing voice disorders, with specific and combined strategies, by a systematic review of the literature. RESEARCH STRATEGIES: Articles published from January, 1980 to April, 2013 were searched in the electronic databases MEDLINE (accessed through PubMed), PubMed, LILACS, SciELO, Scopus and Web of Science. SELECTION CRITERIA: All the articles that presented randomized controlled studies with some type of vocal intervention with teachers as their primary aim were included. Articles that presented subjects with larynx and voice alterations were excluded. RESULTS: As a result of the initial search, 677 studies were identified, five of which followed the inclusion criteria. Four more articles, found in the references of the studies selected for reading of the full text, were included. CONCLUSION: The combined intervention (direct and indirect) presented a significant improvement in vocal quality parameters and self-assessment, even in a short period of time. In other studies, which focused on the comparison between combined and specific interventions (direct or indirect), no differences were observed, although improvements in some of the assessed vocal parameters were described. A limitation of this review is the restriction of the methodological design of the studies, including only randomized clinical trials. The combined vocal intervention presented more significant results than the specific intervention.
Voice; Faculty; Voice Training; Voice Disorders; Larynx; Occupational Health