Evidence on Vocal Interventions in Adults: A Scoping Review

Abstract

To map the evidence on vocal intervention in people over 18 years old. A literature search was conducted using the following electronic databases: Cochrane Library, EMBASE, Latin American and Caribbean Literature on Health Sciences (LILACS), LIVIVO, Pubmed/Medline, Scopus, SpeechBITE, and Web of Science. Gray literature was also used as an information source through searches on Google Scholar, Open Grey, ProQuest Dissertation and Thesis, and the Brazilian digital library of theses and dissertations. Systematic reviews (SR) with a population of individuals over 18 years old were included. The included reviews addressed speech-language pathology interventions in the vocal area with reports of their respective outcome. The methodological quality of the included systematic reviews was analyzed using the AMSTAR II tool. Quantitative analysis was performed by frequency distribution, and qualitative research was analyzed through narrative synthesis. A total of 2,443 references were retrieved, among which 20 studies met the inclusion criteria. The included studies had critically low quality, lacking the use of population, intervention, comparison, and outcome (PICO) components. Among the included SRs, 40% were made in Brazil, 45% were published in the Journal of Voice, and 75% analyzed dysphonic patients. The most frequent intervention was voice therapy (direct therapy associated with indirect therapy approaches). Positive results were observed in most of the outcomes for all studies. Voice therapy was described as inducing positive effects for voice rehabilitation. However, due to the critically low quality of studies, the literature did not enable us to understand the best results for each intervention. Well-designed studies are necessary to clarify the relationship between the intervention goal and how the intervention was evaluated.