Effectiveness of Speech Therapy in Trans Women.

The main aim of this project is to investigate the short-term and long-term effect of speech therapy for pitch and resonance on vocal characteristics, listeners' perceptions and self-perception in trans women using a randomized sham-controlled trial and a longitudinal cross-over design. The goals of speech therapy are selected based on a systematic review and meta-analysis: pitch and resonance.

The first purpose is to determine and compare the short-term effect of two therapy programs Pitch Elevation Therapy (PET) and Articulation-Resonance Therapy (ART), in trans women on (a) acoustic voice characteristics investigating vocal quality, pitch and resonance, (b) listeners' perceptions using a combination of (binary) gender identification and femininity ratings using a Visual Analogue Scale (VAS) and (c) self-assessment investigating the client's satisfaction of the therapy and psychosocial functioning, using a randomized controlled trial.

Hypotheses:

1. Outcome acoustic voice characteristics: Based on studies and our pilot study investigating the immediate effects of resonance and articulation exercises in trans women, a significant increase in all formant frequencies, and an increase in speaking fo is hypothesized after ART. Based on studies, an increase in speaking fo between 10 and 84Hz is hypothesized after PET. The speaking fo and formant frequencies are primary outcome measures.

Vocal training and increasing pitch (during the PET) is associated with increasing vocal load and has a possible negative effect on vocal quality. Monitoring vocal quality in the three groups is therefore important. PET includes gliding tones and consequently can have a possible effect on frequency range. Therefore vocal quality and vocal range parameters are included as secondary outcome parameters. PET and ART are designed to feminize the voice without vocal misuse. Therefore, measurements of vocal quality are hypothesized to remain stable after treatment. After PET, an increase in vocal range is hypothesized. 2. Outcome listeners perceptions: According to the systematic review and meta-analysis of Leung et al., pitch and resonance are the most salient listener perceptions of speaker gender. Based on the results of our pilot study, and other studies, it is hypothesized that both therapy programs, PET and ART, will result in a more feminine speech rated on a VAS. Based on the results of Gelfer et al. we hypothesize that 50% of the participants will be perceived as female after the PET therapy. 3. Outcome self-assessment: Based on a retrospective study, case studies, and another study, significant improvement in psychosocial wellbeing and high levels of satisfaction with the post-treatment voice are hypothesized in both programs.