[Systematic review of delayed auditory feedback effectiveness for stuttering reduction].

PURPOSE: To perform a systematic review of studies related to the effects of delayed auditory feedback on speech fluency in individuals who stutter.

RESEARCH STRATEGY: Concepts of the Cochrane Handbook were followed: formulation of initial question (theme to be reviewed), location and selection of studies (PubMed database) and compatibilization among researchers (aiming to minimize possible citation losses).

SELECTION CRITERIA: The following were excluded: citations in languages other than English, citations that did not allow access to full text, repeated citations due to the overlap of keywords, studies developed exclusively with fluent individuals, case reports, reviews of the literature, letters to the editor, and texts that were not directly related to the theme. Hence, texts that were related to treatment with delayed auditory feedback (DAF) and frequency-altered feedback (FAF) were analyzed.

DATA ANALYSIS: Data were analyzed according to research indicators and according to study quality markers.

RESULTS

The results indicated that the use of altered auditory feedback devices for the reduction of stuttering events still do not have robust support for their applicability. Methodological variability does not allow a consistent answer, or a trend about the effectiveness of the device, to be drawn.

CONCLUSION

Although the limitations in the studies prevent generalizations about the effectiveness of the device for the reduction of stuttering, these same limitations are important resources for future research planning.