Purpose: The aim of this study was to provide a systematic review of the aspects of verbal communication contributing to listener perceptions of speaker gender with a view to providing clinicians with guidance for the selection of the training goals when working with transsexual individuals.
Method: Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) guidelines were adopted in this systematic review. Studies evaluating the contribution of aspects of verbal communication to listener perceptions of speaker gender were rated against a new risk of bias assessment tool. Relevant data were extracted, and narrative synthesis was then conducted. Meta-analyses were conducted when appropriate data were available.
Results: Thirty-eight articles met the eligibility criteria. Meta-analysis showed speaking fundamental frequency contributing to 41.6% of the variance in gender perception. Auditory-perceptual and acoustic measures of pitch, resonance, loudness, articulation, and intonation were found to be associated with listeners' perceptions of speaker gender. Tempo and stress were not significantly associated. Mixed findings were found as to the contribution of a breathy voice quality to gender perception. Nonetheless, there exists significant risk of bias in this body of research.
Conclusions: Speech and language clinicians working with transsexual individuals may use the results of this review for goal setting. Further research is required to redress the significant risk of bias.