Effectiveness of Speech Therapy in Trans Women.
Condition: Transgenderism; Gender Dysphoria; Speech Therapy; Voice Disorder Due to Transsexualism
MeSH terms: Voice Disorders; Communication Disorders; Gender Dysphoria
Study type: Interventional

Summary: 
      One of the greatest hurdles in the transition of transgender persons is that voice, speech
      and communication are not congruent with the desired gender. Since hormone treatment does not
      affect the voice in male-to-female transgender persons (trans women), speech therapy is the
      treatment of choice to develop a more feminine communication. Speech therapy must focus on
      aspects of communication that play an important role in listener perceptions of the speakers
      gender. Results of a systematic review and meta-analysis showed that those aspects are
      primarily fundamental frequency of the voice and resonance. However, effectiveness studies of
      speech interventions in transwomen are extremely limited and show methodological limitations.
      The purpose of this project is to investigate the short-term and longterm impact of speech
      exercises for pitch and resonance on (a) acoustic voice characteristics, (b) listener
      perceptions of femininity using a visual analogue scale and binary gender identification
      (male versus female voice), and (c) self-perception and psychosocial functioning in trans
      women using a randomized sham-controlled trial and cross-over design.
    

Detailed description: 
      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.

      The second purpose of the study is to determine the short- and long-term effects of the whole
      therapy program, consisting of the combination of both PET and ART, in transwomen on (a), (b)
      and (c) immediately after therapy and at 3 months and 1 year using a cross-over design.

      Hypotheses:

        1. Outcome acoustic voice characteristics: Based on a retrospective study and prospective
           studies on small sample sizes investigating long-term outcome of speech therapy, a small
           decrease of the speaking fo is hypothesized in the long-term follow-up after one year.
           The long-term outcome of the formant frequencies remains unclear.

        2. Outcome listeners perceptions: Based on a pilot study, it is hypothesized that the
           listeners perceptions immediately after therapy will not differ from the listeners
           perceptions 3 months and 1 year after therapy.

        3. Outcome self-assessment: Based on the results of a study and because speech is a crucial
           element in the psychosocial functioning of a trans women, an increasing improvement in
           activity and participation after 3 months and 1 year is hypothesized.

      Randomized sham- controlled trial group 1 (n=26): pre sham post 1 PET post 2 ART post 3
      follow-up 1 follow-up 2 group 2 (n=26): pre sham post 1 ARTpost 2 PET post 3 follow-up 1
      follow-up 2

      Study design. A randomized sham-controlled trial will be used to determine and compare the
      short-term effect of PET and ART in trans women. By adding a cross-over design, the effect of
      a combined treatment (PET and ART) can also be investigated, both on the short- and longer
      term.

      Motivation: A randomized controlled trail is considered the most reliable form of scientific
      evidence in efficacy studies. The use of a sham therapy will take into account placebo an
      therapist effects. A cross-over design is used for ethical reasons, so that each subject will
      receive the whole voice feminization approach (PET and ART) in an acceptable time frame.
      Follow-up data are included to determine long-term effects of the intervention and track
      which subjects still need phonosurgery or further behavioral intervention.

      Participants. Sample size. To date, no randomized controlled trials investigated the effect
      of speech therapy in transwomen. Therefore, sample size calculation was based on the study of
      Dacakis. This pilot study gave a minimal sample size of n = 18 participants per group (SAS,
      Power and Sample Size). Minimal sample size was calculated for the fundamental frequency with
      an α level of 0.05, a power of 80%, and a SD of 20 and 15. Taking into account a mean
      drop-out rate of 30%, minimal sample sizes are increased from 18 to 26 participants per
      group. It guarantees a large sample size to perform data-analysis with sufficient power.
      Taking into account the research group's expertise in the field and the accessible
      recruitment via the gender clinic of UZ Gent, a total of n = 78 participants is a very
      feasible number.

      Inclusion criteria and exclusion criteria for the trans women are described further in the
      application.

      The multidimensional voice assessment will be performed by an SLP (different from the
      therapist) with more than 5 years of experience of the research group who is blinded to group
      allocation and study evolution. Assessments will be planned before the treatment (pre),
      immediately after sham therapy (post 1), immediately after therapy 1 (post 2), immediately
      after therapy 2 (post 3) and at three months (follow-up 1) and 1 year (follow-up 2)
      follow-up. All measurements will be performed in a sound treated room (speech lab) at Ghent
      University Hospital at the department of Rehabilitation Sciences.

      Listening experiment.

      Listeners: An equal number of male and female naïve, native Dutch speaking laypersons (n=60),
      aged (and equally spread) between 20 and 49 years old, with a normal hearing will be
      recruited for the listening experiment. All listeners will be blinded to the purpose of the
      study and the gender of the speakers of the speech samples. The hearing levels of all
      listeners will be evaluated by the audiologists of the research team using audiometry.

      Table 1: Number of listeners per age group, gender and task.

      VAS-scale Binary rating M (n) F (n) M (n) F (n) 20-29y 5 5 5 5 30-39y 5 5 5 5 40-49y 5 5 5 5

      Method:

      The listeners, who are blinded to the purpose of the study, will be randomly assigned to 2
      groups to rate audio samples on masculinity/femininity using a VAS (group 1, n=30) and gender
      identification (male voice versus female voice) (group 2, n=30).

      Speech samples: From the speech samples of continuous speech during reading (using a
      phonetically balanced text) the middle sentences (+- 15 seconds) will be selected and used in
      the experiment. For the listening experiment E-prime 3 software is used to randomize and
      present the samples.

      Ratings: The raters will listen once to the samples presented by E-prime 3 software during a
      PowerPoint presentation using a laptop and over ear headphones in a quiet sound treated room.
      They can include pauses to maintain concentration levels. Intensity levels will be presented
      at a comfortable level for the listener (approximately at 70dB at ear level). The listeners
      will also receive 2 other questions (distracting them from the purpose of the study)
      regarding the age and vocal quality of the speakers. They will rate the audio samples of all
      participants (n= 78) at all test moments and of 13 cis-male and 13 cis-female control
      persons. Inter-rater reliability will be calculated. 15% of the samples will be randomly
      repeated to calculate intra-rater reliability.

      Speech therapy procedures. Trans women will be randomly assigned to one of the 2 groups (PET,
      ART) using randomization. All groups will receive the same dosage of individual therapy: 10
      sessions of one hour during 5 weeks. The interventions will have an equal duration (5
      sessions) and will be provided in a different order in both groups: Pitch Elevation Therapy
      (PET) and Articulation Therapy (ART). All therapies, including the sham therapy, will be
      provided by the same experienced therapist of the research group, having more than 10y of
      experience in this field, to control for therapist effects and assure optimal treatment
      fidelity. Interventions will take place in a sound treated room (speech lab) at Ghent
      University Hospital (dep. of Rehabilitation Sciences). PET and ART will be described in
      detail for the publications of this project to ensure replicability. The control group will
      receive information sessions regarding transgender logopaedic and general health care and,
      communication aspects, an active intervention for non-verbal communication skills and
      breathing patterns. Therefore, it is feasible to provide the same duration as the PET and ART
      interventions.

      The same hierarchical structure will be used for both therapy programs and is based on a
      comprehensive literature searching.

      Statistical analysis. Linear mixed model analyses (LMM) (incl. baseline analyses) will be
      used to determine whether there is a difference in evolution between the therapy groups over
      time (interaction effect time*group). Within- and between-group differences will be analyzed
      using post-hoc pairwise comparisons (with Bonferroni correction).
    

Intervention name(s): Pitch Elevation Therapy; Articulation Resonance Therapy; Sham therapy
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Goal: mean fundamental frequency of 180Hz (range 140 and 300Hz); Doses and duration: 5 one hour sessions (5h), 5 weeks
Content:
auditory discrimination of lower and higher tones
pitch glides
pitch glides using straw phonation and resonance tube phonation
practice of higher pitch voice (target: 180Hz) in isolated vowels - syllables - mono and bisyllabic words -phrases - sentences and texts - conversation (generalization to spontaneous speech); Goal: increase in lipspreading, forward tongue carriage, larynx elevation, forward resonance, precise articulation; 5 sessions Doses and duration: 5 one hour sessions (5h), 5 weeks
Content:
auditory and visual discrimination of forward vs backed tongue carriage and lip spreading vs lip rounding)
practice of technique on isolated vowels -syllables -mono and bisyllabic words - phrases - sentences and texts - conversation (generalization to spontaneous speech)
practising larynx elevation through the twang technique, isolated vowels -syllables -mono and bisyllabic words - phrases - sentences and texts - conversation (generalization to spontaneous speech)
forward resonance, focusing on oral forward resonance rather than chest resonance, isolated vowels -syllables -mono and bisyllabic words - phrases - sentences and texts - conversation (generalization to spontaneous speech)
clear, precise articulation and cork exercise; Goal: active sham treatment, 4 sessions Doses and duration: 4 one hour and 15 minutes sessions (5h), 4 weeks
Content:
providing information about vocal function, vocal surgery, vocal hygiene, transgender health care
discussing communication aspects and patterns, possible exercise contexts, communication partners, expectations of voice modification, conversational subjects
active intervention on nonverbal communication (Kinesics, gestures and sign language, facial expression, haptics, proxemics, occulsics, and physical appearance)
practising costo abdominal breathing patterns
Other intervention name(s): PET; ART
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment