Effectiveness of intonation training (Papeleu et al., 2026)

Purpose: This randomized clinical trial investigated the short- and longer-term effects of intonation training on acoustic parameters, listener perceptions, and self-reported outcomes in transgender and gender diverse (TGD) individuals.Method: Twenty-three TGD individuals presumed female at birth (17 nonbinary and six transmasculine) aiming for a more masculine-sounding voice were randomized into two groups. Group 1 completed 4 weeks of intonation training for developing more masculine intonation patterns. Group 2 received 4 weeks of intonation training after 4 weeks of sham training. Recordings were made pretraining, after sham training (only Group 2), after intonation training (Groups 1 and 2), and at follow-up (after 4 weeks of no intervention). Acoustic and perceptual intonation parameters, self-perception of voice, and perception of masculinity/femininity by others were examined. The outcomes were analyzed using linear mixed models.Results: Significant and desired decreases were observed in all acoustic and perceptual intonation parameters (i.e., general and final intonation shifts, general fundamental frequency [fo] range, and fo variation index) across sentence types (i.e., yes/no questions, question word questions, and declarative sentences). Naive listeners perceived participants’ voices as significantly more masculine after intonation training. In addition, the participants reported their voice as significantly more masculine and more aligned with their gender identity. They observed significantly more downward intonation shifts at the end of utterances, significantly less pitch variation, and significantly slower pitch changes.Conclusion: Findings support including intonation in voice and communication training for TGD individuals seeking a more masculine-sounding voice, offering an effective intervention for gender-affirming voice modification.Supplemental Material S1. Intonation training protocol.Supplemental Material S2. CONSORT checklist.Papeleu, T., Oates, J., Tomassen, P., T’Sjoen, G., Leyns, C., Daelman, J., & D’haeseleer, E. (2026). Effects of intensive intonation training in transgender and gender diverse people aiming for a more masculine-sounding voice: A randomized clinical trial. American Journal of Speech-Language Pathology, 35(2), 515–545. https://doi.org/10.1044/2025_AJSLP-25-00238