ACOUSTIC AND PERCEPTUAL OUTCOMES OF VOCAL TRAINING FOR TRANSGENDER WOMEN

Purpose: This study investigated the acoustic and perceptual outcomes of a specific six-week voice training protocol for transgender women, by analyzing acoustic features of speech and voice. The authors sought to establish statistical and clinical significance between speaking fundamental frequency and self-perceptual ratings of communicative experiences, preand post-training. Methods: Speech samples were collected from 10 transgender women. Acoustic variables analyzed for this research include: fundamental frequency (F0) of vowel prolongation, speaking fundamental frequency (SFF) of spontaneous speech, formants (F1 and F2), pitch perturbation quotient (PPQ), relative average perturbation (RAP), noise-to-harmonic ratio (NHR), and intensity. Participants also completed a selfevaluation of communicative experiences using a five-point scale from the Transsexual Voice Questionnaire, Male-to-Female (TVQMtF). Speech samples were collected preand post-training to establish statistical and clinical significance. Results: Statistically and clinically significant gains were found between preand post-training in the areas of F0 in vowel prolongation, and SFF during spontaneous speech. There were generally medium effect sizes for F1 and F2, PPQ, RAP, NHR, and intensity. These analyses were limited by sample size. Results suggest that F0 of vowel prolongation, SFF, SFF variation, formant modification, and intensity are suitable targets for evidence-based practices for transgender women.

iii ACKNOWLEDGMENTS I would like to thank everyone who provided support and guidance to complete this thesis. All mistakes are mine alone. I would first like to thank my advisor and academic supervisor Dr. Leslie Mahler. Her patience, thoughtfulness, and confidence in my abilities helped me to persevere throughout this process. Thank you to Kimberly Dahl, your hard work has provided an opportunity for which I will be eternally grateful. Thank you to Madison Turner, for all of her hard work and patience, I hope this experience was of value. Thanks are due to my thesis committee, from whom I have learned to better myself personally and professionally. I would also like to thank my husband, whose unwavering patience and support has allowed me to change careers, and work toward my personal and professional goals.
Lastly, I am most thankful of all of the participants who found time to take part in this research. The opportunity to meet these individuals is something I will cherish the most from this experience.
iv DEDICATION For my transgender friends and family, and all members of the LGBTQ+ community.
v    Selecting appropriate speech and voice targets for trans women is vital to establishing an effective protocol for training. Presentation of a gender congruent voice as a desired outcome for training is often a goal for trans women seeking voice training. Objective data and perceptual data are needed to clearly comprehend how specific approaches to training affect speech and voice.

Purpose
The purpose of this study is to contribute to the knowledge base and provide data to evaluate the efficacy of a specific speech and voice training protocol. It examines the impact that this protocol has on acoustic features of 10 trans women pre-and posttraining. The specific aims of the study are: 1. Measure acoustic and perceptual variables of voice and speech related to gender identity immediately before and immediately after six weeks of a transgender voice training protocol. a. Hypothesis: Changes in acoustic variables will result in speech and voice characteristics that more closely align with cisgender women post-training.
2. Determine whether quantitative changes in acoustic features related to gender identity correlate with self-perceptual measures of voice and speech.
a. Hypothesis: As changes in acoustic variables more closely align with cis-gender women post-training, voice satisfaction will improve.

Significance
This study contributes to the literature in numerous ways. First, it involves analyses of speech and voice measures, some of which have received little scrutiny in past studies of the trans population. Second, it compares pre-and post-training data using a self-perceptual rating of voice. Third, it provides data regarding vocal characteristics in sustained vowel phonation and connected speech during spontaneous productions in salient speech contexts. This study provides insight into appropriate goals and objectives that are likely to promote generalization outside of training.
Lastly, this research identifies differences in pre-and post-training speech and voice variables. Determining the statistical and clinical significance of these differences are essential to providing information for speech language pathologists, and to establish targets that are likely to be most effective in helping trans individuals to achieve their goals of gender-congruent communication.

BACKGROUND
Previous research of training programs for transgender women is lacking in the current literature. Research that is available does not consistently include a clearly described and specific training protocol. This chapter provides a description of the previous literature and establishes the need to clarify and further establish the need for additional research on voice training for trans individuals.

Voice and gender identification
Several vocal characteristics have been studied in previous research studies to identify whether they make significant differences in gender identification.  analysis between vowel formant frequency, gender perception, and ratings of femininity indicated minimal clinical significance between acoustic features and femininity-masculinity rating scale. However, results did demonstrate significant differences between speaking fundamental frequency (SFF) and upper limit of SFF, as subjects with high SFF (mean 187 Hz) and SFF limit (165-209 Hz) were more often perceived as female. The study also noted that subjects' progress varied as a result of differences in the stage of transition (e.g., initial, medial, or final stages of transition).
Research findings by Gorham-Rowan and Morris (2006) revealed that ratings of trans women by unfamiliar listeners were most likely to be identified as female when speaking with an SFF of 160 Hz and greater. Increasing pitch along with other voice and speech modification strategies, such as modifying loudness (Hancock & Garabedian, 2012), modifying (Quinn & Swain, 2018), and following healthy vocal hygiene practices have been shown to increase the likelihood of gender congruent speech perception (Dahl and Mahler, 2019).

Acoustic features of gendered voice
Cisgender individuals, those who identify with the gender they were born with, display specific vocal characteristics which coincide with societal norms. These features provide acoustic information to listeners and allow them to perceive a voice as masculine or feminine. Cisgender women's SFF is generally produced at an average of 250 Hz (Kumar, Banumathy, Sharma & Panda, 2019).
Post-pubescent males tend to have much longer and thicker vocal folds and a larger vocal tract (Kawitzky and McAllister, 2020) when compared to women. Trans women who speak at an F0 lower than 160 Hz have a greater chance of being misgendered when physical cues (i.e., physical presentation) are not available (i.e., during telephone calls) (Kawitzky and McAllister, 2020). Podesva and Callier (2015) described voice quality as "the extragrammatical suprasegmental properties of speech resulting from the configuration of the vocal apparatus." Resonance plays a key role in voice. The glottal wave, created by vibration of the vocal folds, travels through the vocal tract. The vocal tract modifies the signal heard by listeners. This altered soundwave is what listeners perceive as the speaker's voice. Feminine voices tend to contain higher formants, which provide auditory cues to listeners and allow them to perceive the gender of the speaker as female (King, Brown, and McCrea, 2012). Formants vary by speaker, specifically in vowel production. They rely on length and shape of the vocal tract and tongue placement. Formants are an important factor in the perception of gender (Kawitzky and McAllister, 2020).

Self-perception of the feminine voice
Self-perception of vocal femininity is a vital factor in self-acceptance of an individual's identity (Lara and Peterson, 2018). Perceptual tools used to establish a self-rating of vocal femininity include the Transsexual Voice Questionnaire -Male to Female (TVQMtF) and the Transgender Self-Evaluation Questionnaire (TSEQ). Both questionnaires contain similar questions concerning social interaction, emotions, gender and identity, speech production effort, physical aspects, and pitch (Davies and Johnston, 2015). Dahl and Mahler (2019) found a moderately positive correlation between self-ratings and maximum SFF, utilizing the TVQMtF. Casado, Rodriguez-Parra, and Adrian (2016) used the TSEQ in their research. They noted a moderately significant correlation between SFF and the TSEQ score.
Few studies have sought to establish relationships between acoustic features and self-perception beyond SFF. Hancock and Garabedian (2013) studied 25 cases to correlate self-perception with SFF and semitone ranges, which produced conflicting results. Participants who presented an SFF within a masculine range reported high satisfaction with their voice. This finding suggests that even those who did not achieve their SFF goals developed self-confidence by using a higher pitch. Therefore, a study of training outcomes for trans women should include a combination of quantitative assessment of acoustic vocal features and a qualitative assessment of self-perception to understand participant's self-perception of their communication and communication experiences. This study will use acoustic measures and measures of self-perception to gain a comprehensive understanding of the outcomes of speech and voice training. This study contributes to the literature by measuring changes in vocal characteristics of trans women following a specific training protocol. Analyses will permit the comparison of changes in acoustic variables and self-reported satisfaction in the areas of voice and communication. The study will allow examination of the effect of training and identify how it affects acoustic variables. It will assist in the development of a specific protocol for a speech-language pathologist to provide best practices and appropriate treatment goals for trans women.

Research design and study sample
This study is a multiple single-subject experimental research design that includes analysis of pre-and post-training data for 10 trans women. Eligibility criteria for participants were: (1) identification as a trans woman, (2) aged 18-78 years, and (3) no history of laryngeal trauma or surgery. Vocal changes related to aging and surgery or trauma are likely to affect acoustic and self-perception measures of voice, resulting in confounding study results. Consequently, these confounding variables resulted in a participant's exclusion from the study.
The participants ranged in age from 25 to 60 and the amount of time spent in transition varied. Table 3.1 provides a summary of descriptive information about the participants.

Participant Perceptual Self-ratings
Each participant completed the Transsexual Voice Questionnaire -Male to Female (TVQMtF) during the initial evaluation and post-training evaluation. The TVQMtF results were used to address participants' self-perception of their voice by utilizing a five-point Likert Scale to establish a rating of communicative experiences.
The same scale was presented during an exit interview for each participant. Ratings Davies and Johnston (2015) also studied the validity of the TVQMtF and determined that 24 percent of the items on the questionnaire did not pertain to voice but were considered appropriate with regard to the experiences of trans women. Reliability of the TVQMtF was found to have internal consistency, and excellent test-retest reliability (Dacakis et al., 2013).

Training Protocol
Voice training took place three times per week, for 50 minutes per session, for six weeks. Sessions consisted of two individual sessions and one group session each week. Training was provided by clinicians instructed in the area of voice. Based on the pre-training evaluation and data collection, a target pitch was established for each participant. Each session began with exercises for participants to prepare their vocal folds for healthy voice production of an increased pitch. Vocal warmups consisted of semi-occluded vocal tract exercises, sustained /i/, and pitch glides.
Participants produced phonation through a straw during the semi-occluded vocal tract exercises, to reduce vocal fold tension while ranging from highest to lowest comfortable pitch for 5-10 seconds. During sustained /i/ exercises, participants were instructed to produce and sustain the vowel /i/ at their target pitch for 5 to 10 seconds.
The final exercise, pitch glides, required participants to produce the /i/ sound again and gradually increase pitch as high as comfortably possible. The exercise was then repeated while decreasing the pitch as low as comfortably possible.
Vocal strategies from non-speaking tasks were integrated into functional speech, using phrases and sentences determined by the participants based on their daily communication. Participants read their functional phrases using a higher SFF and greater variation of pitch. These sentences consisted of phrases which the individual stated on a regular basis to promote generalization of the participant's targeted SFF. The remainder of the sessions consisted of various tasks and activities to encourage spontaneous speech productions utilizing the participant's targeted SFF.
Additional tasks targeted other verbal and nonverbal characteristics of communication (i.e., intonation, light articulation, gestures, and body language). At the conclusion of each session, clinicians discussed proper vocal hygiene practices (i.e., proper hydration, no shouting, vocal rest, etc.). Vocal hygiene education allowed participants to maintain adequate vocal health during the six-week training period. Clinicians also provided carry-over assignments, which involved communicating with a loved one or making a telephone call using their targeted SFF.
Group sessions involved three to six participants. Each group session began with participants taking turns practicing their targeted pitch while phonating /i/ for five seconds to calibrate to the desired SFF. The remainder of the session involved tasks which required participants to ask questions, describe items, express opinions, and contribute to conversations. Clinicians monitored the SFF of each participant while they spoke and provided verbal and/or gestural cues as needed to adjust participants' pitch. The main goal of group sessions was to maintain target SFF during spontaneous speech in a supported environment that more closely approximated functional communications situations. While individual sessions directly focused on target SFF, intonation variation, and the individual needs of each participant.

Data Analyses
F0, pitch perturbation quotient (PPQ), relative average perturbation (RAP), and noise-to-harmonic ratio (NHR) were computed for vowel prolongation samples from each evaluation. F0 was analyzed utilizing the Multi-Dimensional Voice Program (MDVP), which provided a mean F0 and standard deviation as a variation measure.
PPQ analyzes the relative variability of frequency from point to point within a speech sample, with a smoothing factor of 5 points. RAP analyzes the relative variability of frequency from point to point within a speech sample, with a smoothing factor of 3 points. These measures are commonly referred to as jitter and provide information about vibratory patterns of the vocal folds. NHR defines the average ratio of inharmonic spectral energy within a high frequency range (1500-4500 Hz) to the harmonic spectral energy within the SFF range (70-4500 Hz). This defines the amount of noise present within a signal (Dejonckere et al., 2007). Table 3.2 lists the dependent variables and the analysis tools used along with measures that were analyzed, the task from which the values were derived, and software utilized. To ensure inter-rater reliability, 20 percent of the samples were analyzed by a speech-language pathology graduate student unaffiliated with the study. Differences between pre-and post-training data were determined via dependent, two-tailed t-tests. The above measures were also correlated with the following variables: (1) TVQMtF results pre-voice training and; (2) TVQMtF results post-voice training. A non-directional hypothesis is reasonable for research on voice and gender, affirming the use of a two-tailed test. Voices of adult females are characterized by increased pitch (Oates & Dacakis, 2015), higher vowel formants

RESULTS
This chapter presents the results for each of the variables of interest in this study. The data collected are summarized in the tables below. These data include: (1) acoustic measures collected from speech samples of trans women, and (2) self-ratings of voice femininity. The results related to each research aim of this study are also presented.

Summary of the data
This study analyzed acoustic variables of voice and speech and self-perceptual  P-values for F0 of vowel prolongation revealed statistically significant increases (p = <0.01 to 0.02) across all participants. Effect size analyses revealed a large effect size between F0 of vowel prolongation pre-and post-training for all vowels (r = 0.47 to 1.00). F0 of vowel prolongation was higher post-training than pretraining. The highest recorded frequencies were not associated with any single vowel.  There were statistically significantly increases in SFF for 9 out of 10 participants during the picture description task (p = <0.01 to 0.05), and for 7 out of 10 participants for the monologue task (p = <0.01 to 0.04). Effect size was calculated for picture description and monologue using Cohen's (d) and Effect size (r). The effect size was large for 6 out of 10 participants for picture description (r = 0.30 to 0.67).
The remaining four samples had a low-to-medium effect size (r = 0.11 to 0.23). Effect size was large for only 2 of 10 participants for monologue samples (r = 0.40 to 0.46).     Analyses of RAP effect sizes closely followed the trends of PPQ analyses likely due to the fact that is it also a measure of regularity of vocal fold vibration.

NHR analyses revealed decreases in values across all participants' pre-and
post-training. NHR is a measure of a vocal quality perceptually known as breathiness (Dahl and Mahler, 2019 , and one had no effect (r = 0.00). For the vowel /u/, five participants had large effect sizes (r = 0.43 to 0.71). Three participants were determined to have medium effect sizes (r = 0.28 to 0.34). One participant had a small effect size (r = 0.21), and one participant had no change (r = 0.00).   increased post-training compared with pre-training. All participants produced speech at a gender and age-appropriate intensity level for conversation (Yiu and Yip, 2016).
Two-tailed paired-sample t-tests for this variable revealed statistically significant results (p ≤ 0.05) for 19 out of 24 vowels, and five out of 16 spontaneous speech samples. The researchers found that six participants had statistically significantly increased intensity during the production of the vowel /a/, seven participants had statistically significant increases in intensity during the production of the vowel /i/, and six participants demonstrated statistically significant gains in intensity during the production of the vowel /u/.
The analysis of spontaneous speech samples resulted in statistically significantly increased intensity for four participants during the picture description task. One participant showed statistically significant increased intensity during the monologue task. Effect sizes for intensity were also calculated for both tasks. Analysis of the picture description task revealed large effect sizes for six participants (r = 0.51 to 0.78). Two participants produced a medium effect size (r = 0.28 to 0.33), and one participant produced a small effect size (r = 0.14). The monologue speech task also demonstrated increases in intensity post-training. Three participants had large effect sizes (r = 0.51 to 0.46), and one participant had a large effect size (r = 0.42). One participant had a medium effect size (r = 0.27), and 3 had little effect (r = 0.04 to 0.09).   The first aim of this research sought to identify the impact of a specific six- week training protocol on voice and speech variables related to gender identity. These variables include: (1) F0 of vowel prolongation, (2) SFF, (3) SFF variation, (4) F1 and F2, (5) PPQ, (6) RAP, (7) NHR, (8) vocal intensity, and (9) self-perception of voice and communication. We conducted paired t-tests to determine whether, on average, there was a change in acoustic variables from pre-to post-training.
Analyses revealed statistically and clinically significant gains, specifically in F0 of vowel prolongation for all participants. There were also clinically significant increases in F0 of vowel prolongation and SFF of spontaneous speech productions in six out of ten participants. Formant frequencies were inconsistent across participants and vowels. Analyses resulted in statistically and clinically significant gains in frequency of F1 in five participants for the prolongation of the vowel /a/, six for the vowel /i/, and six for the vowel /u/. Analyses of F2 revealed statistically and clinically significant increases in frequency of two participants for the prolongation of the vowel /a/, seven for the vowel /i/, and four for the vowel /u/.
PPQ and RAP followed similar patterns, which varied by participant. For the vowel /a/, there were statistically and clinically significantly decreased measures of breathiness for seven out of nine participants. Participants exhibited statistically significantly increased breathiness for prolongation of the vowel /i/ in two out of nine participants, and three out of nine for the prolongation of the vowel /u/. Clinically significant results were present in four out of ten participants for the vowel /i/ and six out of ten participants for the vowel /u/. Three participants demonstrated statistically significantly increased values upon analysis of NHR during the prolongation of the vowel /a/ in two out of ten participants, two out of ten for the vowel /i/, and five out of ten for the vowel /u/. Clinically significant increases in the analyses of NHR were revealed for two out of ten participants during the prolongation of /a/ and one out of ten participants for the vowel /u/. Medium-to-small effect sizes for the prolongation of the vowel /i/ were not deemed clinically significant.
There were statistically significant increases in intensity across the prolongation of all three vowels (/a, i, u/) for six out of eight participants samples.
Four of the six participants who presented statistically significant gains in intensity, also presented with clinically significant gains. Intensity of spontaneous speech varied more than individual vowel prolongations. Three out of eight participants presented statistically significantly increased intensity during the picture description task, and one out of eight resulted in statistically significantly increased measures of intensity during the monologue task. Clinical significance was determined for five out of eight participants during the picture description task, and four out of eight showed clinically significant increases in intensity during the monologue task, post-training.
Analyses of acoustic measures of speech and voice produced statistical and clinical significance within each participant. Given these results, the researchers determined that a specific six-week speech and voice training protocol had statistically and clinically significant effects on trans women's speech and voice.

Determine whether quantitative changes in acoustic features related to gender identity relate to perceptual measures of voice and speech.
The TVQMtF was administered to each participant during the initial interview and exit interview. Self-scoring was analyzed utilizing the following six categories provided by Davies and Johnston (2015); (1) social interaction, (2) emotional components of voice identity, (3) gender and identity, (4) effort in producing a desired voice, (5) physical aspects of voice production, and (6)

Summary of results
The results of the current study revealed that a specific six-week training protocol resulted in statistically significant changes in acoustic variables of speech and voice that were clinically significant based on large effect sizes. Average because it is a lax vowel, and requires little tension on the articulators, which allows the participants to focus more on sound production at the level of the vocal folds (Shrivastav, et al., 2011). The vowels /i/ and /u/ require manipulation of the glottal wave as it travels through the vocal tract, demanding more focus on the articulators that are required to create each sound. Loss of focus on voice production could result in increased jitter values (Shrivastav, et al., 2011 (Kang et. al., 2018). In the case of this study, voice training may also be an underlying factor of increased NHR due to physiological changes in vocal production. In an attempt to rule out other factors, clinicians provided education regarding vocal hygiene to each participant. These findings are a novel product of the The six-week training protocol may have had an effect which allowed participants to feel confident in their communicative abilities, thus, improving emotion toward communication skills.
The gender and identity subcategory also demonstrated overall gains (mean scores decreased from 15.10 to 10.20) post-training. Two participants reported an increase in scores (increases of +4.00 and +5.00). The gender and identity subcategory included questions such as "My voice makes me feel less feminine than I would like," and "My voice doesn't match my physical appearance." Improvement in scores of this subcategory support an idea that voice training allows participants to practice and experiment with their voice in a safe, judgement-free place (Davies and Johnston, 2015). This, in theory, will provide opportunities for the trans woman to become more comfortable and attuned to her gender identity post-training.
Social interaction is likely an area of concern for many trans individuals. Gains in this subcategory were the most inconsistent among participants (mean scores decreased from 17.40 to 12.70). Three participants reported increased scores (increases of +11.00, +3.00, and +1.00) and one participant reported no change (+/-0.00). These findings are particularly interesting because societal norms, form expectations to which everyone is expected to subscribe. The manner of which social interactions take place are shaped by learning from experiences within society.
Stigmas are formed by those who express distain for individuals who go against the norm (Levitt, 2019). It is possible that these scores were determined by each participant's individual experiences with social norms or interaction, hence the variation in scores.
Improvement in the subcategory of pitch were medial in terms of subcategory standing (mean scores decreased from 11.6 to 8.2). Two participants reported increased scores (increases of +5 and +1), and one participant reported no change in score. The results of this subcategory reveal that participants showed an increased satisfaction in their production of a pitch produced in a range that society considers to be more feminine. These findings are especially interesting because pitch is possibly the most salient perceptual variable in speech (Davies and Johnston, 2015), it was surprising to learn that many participants reported less significant differences than in other subcategories. Statements in the TVQMtF associated with this subcategory included, "The pitch of my speaking voice is too low," and "The pitch of my voice is unreliable." Perceptually, for individuals who are unfamiliar with voice production, it is difficult to distinguish between which aspects of phonation (i.e., larynx, vocal tract, etc.) are the most prominent in pitch. So, one may assume that while answering these questions, the participants in this study have a superficial understanding of the term

Limitations
Results of this study are based on a small sample size. With regard to the probability of a type I error (false positive), this study is most reliable in identifying large effect sizes between pre-and post-training data for fundamental frequency. This study could not detect causation, so conclusions regarding what aspects of the training caused changes in each variable cannot be made.
This study sought to measure the effect of a specific six-week speech and voice training protocol for trans women. This study was a multiple single-subject design in which participants served as their own control. Nevertheless, the findings of this study may not relate to individuals who subscribe to another gender identity, including trans men and gender-nonconforming persons.
This study did not assess correlations between acoustic features of speech and voice and perception of gender by unfamiliar listeners. It also did not take into account participants' education level, percentage of time that participants present as their true gender, or access to support (i.e., family involvement, medical services, etc.) (Dahl and Mahler, 2019;Duthie, 2018). These factors could promote carry-over of gains achieved during training and should be included in future studies.
Speech samples were analyzed during several tasks; (1) vowel prolongations (/a, i, and u/), (2) spontaneous speech productions of picture description and monologue tasks. While vowel productions provide a great deal of insight into the acoustic characteristics of an individual's voice, it does not measure other aspects of speech, which contribute to gendered communication. (Quinn and Swain, 2018). In this study, spontaneous speech samples were useful for measuring changes in pitch during a less structured task. However, it is not representative of conversational speech, which is likely to vary more than describing a picture or answering a single question for a minute of sustained monologue (Podesva and Callier, 2015).
Self-perception of communication abilities is highly subjective. Many participants knew little-to-nothing about voice production before training. Through participant education, some participants may have become more critical of their voice, which may have some influence on the scores reported by participants. For future research, additional ratings and scales, such as the Census Auditory-Perceptual Evaluation of Voice (CAPE-V), and Grade, Roughness, Breathiness, Asthenia, Strain scale (GRBAS) may be beneficial as a supplement to the TVQMtF (Hancock and Garabedian, 2013). Correlations between individual TVQMtF scores and individual acoustic variables may provide insight into the effect of training on individual participants. It may also be beneficial to clinicians to develop a questionnaire for family or loved ones, to further understand how participants' speech and voice impact home life. It also allows participants' family members or significant others to evaluate communicative abilities outside training rooms and provide a clearer picture of how participants use their voice in activities of daily living.
Lastly, this study performed quantitative acoustic analyses of trans women's voices and compared the results with qualitative information regarding participant's perceptions of their voices. However, this study did not consider the different experiences of each individual. Lack of insight into individual cultural norms, and other societal and linguistic elements may have some effect on the outcomes of this study. Additional research is necessary to further understand how these factors affect acoustic characteristics of speech and voice, and self-perception.

CONCLUSIONS
This study examined the effect of a specific six-week training protocol for trans women on speech, voice, and self-perception of communication. The results revealed that training had statistically and clinically significant effects on several variables associated with gendered communication. Voice training had the greatest influence on fundamental frequency of vowel production and spontaneous speech during picture description and monologue tasks. This study also found that a specific six-week training protocol also had a significant effect on self-perception of aspects of gendered communication. Training appeared to increase self-confidence in most participants, but confidence is difficult to quantify from a self-reported questionnaire alone. Overall, mean speaking fundamental frequency, maximum pitch, and variation of intonation were determined to be appropriate targets in an evidence-based voice training program for trans women.
Inconsistency in results of vowel formants and acoustic measures of vocal fold vibration and breathiness suggest that targeting these variables did not produce statistically significant changes toward greater female gender identity, but effect size analyses supported strong clinical significance. Previously published studies identified that addressing pitch is vital to gendered communication .
These studies, however, did not provide in-depth descriptions of the protocol implemented. Additional research is necessary to aid in treatment planning and clinical decision making for speech language pathologists. evidence-based practice. This is an ongoing process in which clinicians should continually seek knowledge about how to best serve their clients. Societal acceptance of a person who lives outside the established norms is vital to the existence of the LGBTQ+ community. Self-acceptance is an internal challenge that each individual must face, though every person's experience is unique. As the cultural norms begin to evolve to be more open and accepting, it the speech language pathologist's responsibility to recognize the communicative needs of this growing community. The results of this study contribute data to identifying possible training targets for trans women. Further research is needed to examine the most effective speech and voice training strategies and tools to evaluate training outcomes.