Letter to Editor Regarding the Article Entitled "Treatment Effects for Dysphagia in Adults with Multiple Sclerosis: A Systematic Review".

This letter is written to inform an important error in the methodology section of a systematic review article entitled "Treatment Effects for Dysphagia in Adults with Multiple Sclerosis: A Systematic Review" by Dalal Alali et al., which consequently resulted in a precise paradox probably and inadvertently affecting the search strategy, results, discussion, and/or conclusion of this systematic review.

The Effect of Bimaxillary Orthognathic Surgery on Voice Characteristics in Skeletal Class 3 Deformity Patients: An Evaluation Using Acoustic Analysis.

ABSTRACT: The aim of this study was to analyze the effects of bimaxillary orthognathic surgery on the acoustic voice characteristics of skeletal class 3 patients. All healthy nonsyndromic patients with Class 3 deformity who were eligible for bimaxillary orthognathic surgery, were included in this before and after quasi-experimental study. This experiment's main intervention was mandibular setback surgery by bilateral sagittal split osteotomy plus maxillary advancement using LeFort 1 osteotomy. Age, sex, and intraoperative jaw movements were recorded. Acoustic analysis of voice samples (vowels /a/ and /i/) was performed with Praat software as outcome variables. The formant frequencies (F0, F1, F2, and F3) of these vowels were extracted 1 week preoperatively (T0), 1 and 6 months (T1, T2) postoperatively by a speech therapist. The significance level was set at 0.05 using SPSS 19. The study sample comprised 20 patients including 11 women (55%) and 9 men (45%) with a mean age of 31.95 ±â€Š4.72 years. The average mandibular setback and maxillary advancement were 3.30 ±â€Š0.86 and 2.85 ±â€Š0.74 mm, respectively. The fundamental frequency (F0) and the first, second, and third formants (F1, F2, F3) of vowels /i/ and /a/ were significantly decreased over time intervals, postoperatively (P < 0.05). The finding revealed that bimaxillary orthognathic surgery (maxillary advancement and mandibular setback with bilateral sagittal split osteotomy) might reduce the acoustic formant parameters of voice to the normal frequency ranges, in patients with class 3 skeletal deformities. More clinical trials with greater sample sizes and long-term follow-ups are suggested in the future.

Comparative Study of the Effect of Experience on Auditory Processing Abilities in Voice Therapists and Other Speech-Language Pathologist in Auditory Perceptual Judgment of Voice.

OBJECTIVE: This study aimed to compare the effect of experience on central auditory processing skills in voice therapists and other Speech-Language Pathologists in the auditory perceptual evaluation of voice. STUDY DESIGN: This research is a descriptive-analytical cross-sectional observational study. METHODS: Our study population includes three groups; first-year speech-language pathology students who have not undergone any training or education in the evaluation of auditory samples (group 1; n = 10), Speech-Language Pathologists who do not have any activity in the field of voice disorders (group 2; n = 10), and therapists who have at least 2 years of experience in auditory-perceptual judgment (group 3; n = 10). Initially, the participants underwent a basic audiological evaluation (Pure Tone Audiometry, Speech Recognition Threshold, Speech Discrimination Score, tympanometry, and acoustic reflex) to assess peripheral hearing. In the next step, the auditory processing skills of the participants were evaluated with the Buffalo model (staggered spondaic word (SSW) test, phonemic synthesis test (PST), speech in noise (SPN) test). In the third step, four recorded voice samples of patients with voice disorders and healthy individuals were randomly selected for auditory perceptual judgment. These samples were the same for all participants. All the voices were previously subjected to auditory perceptual analysis by two Speech-Language Pathologist who had at least 6 years of experience in the evaluation and treatment of voice disorders; the voices were played for participants to assess auditory perception using the grade, roughness, breathiness, asthenia, strain (GRBAS) scale. RESULTS: All subjects had normal hearing and auditory processing abilities but there were some differences among the groups in processing skills. A difference was found in the SSW-qualifier and SPN-R components between the three groups. The third group had significant differences with the other two groups in the evaluation of auditory perception in the components of R, B, and S (from the GRBAS scale) in voice number one, and the components of G, R, and A in voice number three. In voice number two, there was a correlation between the SSW order effect component and the G component, as well as between the PST component and the A component. In voice number three, there was a correlation between the SPN-L component and the G component, and between the SSW condition, SSW qualifier, and SSW All errors components with the S component. In voice number four, there was a correlation between the SSW-RC, SSW-LC, SSW condition, SSW competing, and SSW order effect components with the A component. Lastly, there was a correlation between the SSW order effect and SSW type A components with the R component in voice number three in group three. CONCLUSION: The results of the present study indicate that experience has an impact on auditory processing skills and the participants of the third group, who had more experience in the evaluation of voice disorders obtained better scores than the other two groups in the auditory processing skills. Additionally, the level of experience is related to the accuracy of auditory perceptual judgment of voice. The participants of the third group performed better than the other two groups, and the performance of the first and second groups was almost the same.

Investigating the Effects of Warm-up Exercises on Acoustic Characteristics of Voice in Female Gym Coaches.

INTRODUCTION: A plethora of vocal enhancement and rehabilitation programs for voice professionals define vocal exercises irrespective of analyzing their effects on the specific population on which they are applied, in the established dose and often without considering the presence and absence of vocal alteration. So, in this study we investigated the impact of warm-up exercises (WUE) on the acoustic features of the gym coaches. OBJECTIVE: To determine the effectiveness of WUE on the acoustic characteristics of the voice in gym coaches. STUDY DESIGN: This was a Quasi-experimental control group design study. METHOD: The study was carried out through participation of forty-five female gym coaches with a mean age of 31.4 years (range: 19-44 years) in Mashhad gym salon. Participants were recruited into two conditions. In the first condition, participants did not receive the exercises for a week and were acoustically evaluated at the beginning and end of the week. In the second condition, participants received the exercises once a day for a week and were acoustically evaluated at the beginning and end of the week. Voice samples were included: at least 3 vowels / a / for at least five seconds. The voice samples analyzed by the Praat software recorder (Version 6.0.23) were collected to detect the acoustic characteristics of voice including fundamental frequency (f0) (Hz), jitter (%), shimmer (dB) and noise to harmonic ratio (NHR) (dB). Finally, the data obtained from these two condition were compared. RESULTS: After WUE, a significant increased f0, decreased jitter, decreased shimmer and decreased NHR were measured. (p-value < 0.005). CONCLUSION: The WUE had an immediate positive effect on acoustic characteristics of voice)f0, jitter, shimmer and NHR(in the short term and this study suggests that the WUE is an effective technique for enhancing the overall voice quality of gym coaches.

Comparative Investigation of Laryngeal Palpation Scale Between Primary and Secondary Muscle Tension Dysphonia.

OBJECTIVES: Muscle tension dysphonia (MTD) is a condition that is often assessed through palpation examination. The laryngeal palpation scale (LPS) is a reliable and valid tool developed to evaluate patients with MTD. MTD is classified into primary (without tissue reactions) and secondary (with tissue reactions). Primary MTD is caused by muscle hyperfunction, while maladaptive compensation typically leads to secondary MTD. The objective of this study was to compare the LPS scores between primary and secondary MTD. METHODS: This study is a cross-sectional analytical comparative study. It included 39 participants (10 men and 29 women) who were divided into two groups: primary MTD and secondary MTD with mass lesions (20 with primary MTD and 19 with secondary MTD). Each type of MTD was diagnosed by a qualified otolaryngologist. The participants were assessed using the LPS, which comprises 45 variables evaluated across three subscales. RESULTS: The results of the current study showed that there is a difference between the primary MTD and secondary MTD in the subscale of patients with symptomatic complaints of the item pain at rest/speaking (Pv = 0.001) and pain level (Pv = 0.019) and the subscale of palpation the item cricothyroid (left) in dynamic conditions (tenderness; Pv = 0.013). In other LPS items, no difference was observed between primary MTD and secondary MTD in all three subscales (Pv ≥ 0.05). CONCLUSIONS: The LPS scores for pain items during rest/speaking and the pain level, as well as the left cricothyroid (tenderness) item, were different between the primary MTD and secondary MTD groups. However, the other LPS items did not show any difference between the primary MTD and secondary MTD groups. Further investigation on palpation findings with LPS in larger samples in both groups and with objective measurements such as electromyography are recommended.

What Is the Effect of Maxillary Impaction Orthognathic Surgery on Voice Characteristics? A Quasi-Experimental Study.

Background: Regarding the impact of orthognathic surgery on the airway and voice, this study was carried out to investigate the effects of maxillary impaction surgery on patients' voices through acoustic analysis and articulation assessment. Methods: This quasi-experimental, before-and-after, double-blind study aimed at examining the effects of maxillary impaction surgery on the voice of orthognathic surgery patients. Before the surgery, a speech therapist conducted acoustic analysis, which included fundament frequency (F0), Jitter, Shimmer, and the harmonic-to-noise ratio (HNR), as well as first, second, and third formants (F1, F2, and F3). The patient's age, sex, degree of maxillary deformity, and impaction were documented in a checklist. Voice analysis was repeated during follow-up appointments at one and six months after the surgery in a blinded manner. The data were statistically analyzed using SPSS 23, and the significance level was set at 0.05. Results: Twenty two patients (18 females, 4 males) were examined, with ages ranging from 18 to 40 years and an average age of 25.54 years. F2, F3, HNR, and Shimmer demonstrated a significant increase over the investigation period compared to the initial phase of the study (P <0.001 for each). Conversely, the Jitter variable exhibited a significant decrease during the follow-up assessments in comparison to the initial phase of the study (P< 0.001). Conclusion: Following maxillary impaction surgery, improvements in voice quality were observed compared to the preoperative condition. However, further studies with larger samples are needed to confirm the relevancy.

The acoustic voice quality index, version 2.06 and 3.01, for the Persian-speaking population.

INTRODUCTION: Dysphonia assessment includes approaches like acoustic analysis, which is non-invasive and easy to use and provides an understandable numerical output. The Acoustic Voice Quality Index (AVQI) is an acoustic model that can detect dysphonia. The Persian language is spoken by around 70,000,000 native speakers. Since AVQI versions 2.06 and 3.01 have not been validated for the Persian yet, this study investigated their concurrent validity and diagnostic accuracy among the Persian-speaking population. METHODS: This scale development study was conducted from 2020 to 2021 on 180 normophonic and dysphonic native Persian-speaking residents of Mashhad, Iran. Five raters rated the samples by auditory-perceptual-judgments, including Grade from the Grade-Rough-Breathy-Asthenic-Strained (an ordinal scale) and the overall dysphonia severity from the Persian version Consensus Auditory Perceptual Evaluation of Voice (a continuous scale) to investigate both versions' concurrent validity. The intra- and inter-rater reliability and concurrent validity were evaluated for both scales. Both versions' diagnostic accuracy was assessed by the receiver operating characteristic, and the optimal thresholds were determined. RESULTS: AVQI-version-2-Persian thresholds of 3.47 and 4.04 provided sensitivity of 88.30% and 85.53% and specificity of 79.07% and 85.58% by the ordinal and continuous scales, respectively. AVQI-version-3-Persian thresholds of 3.07 and 3.03 also rendered sensitivity of 74.47% and 85.53%, and specificity of 97.67% and 91.35% by the ordinal and continuous scales sequentially. CONCLUSION: The significant values of concurrent validities and diagnostic accuracies of both versions of AVQI-Persian confirmed that it can discriminate between normal and pathological voices among the Persian-speaking population. Hence, it can be used for screening or diagnosis purposes.

Persian Translation, Validation and Reliability of the Voice Handicap Index-Throat (VHI-T).

OBJECTIVE: The aim of the present study is to validate, and assess the reliability of the Persian version of Voice Handicap Index-Throat (VHI-Tp) as a self-reported questionnaire for patients with throat problems that could make the patients' estimation of the throat discomforts possible. It is a subscale to be used independently. STUDY DESIGN: This is a cross-sectional study. MATERIALS AND METHOD: During this study, the VHI-Tp was administered to120 patients with throat problems related to laryngeal discomfort (51 male and 69 female, age range: 30-60 years).The diagnosis of Voice disorder was performed by an ENT physician based on video-laryngoscopy evidences and medical examination. To assess the content validity, the questions were first given to 15 experts to comment on content applicability and relevance through a Likert scale. Eighty patients rated its importance to detect face validity. To evaluate the concurrent validity, the same 80 patients completed both the VHI-Tp as well as the Persian version of Voice Symptom Scale. The VHI-Tp total scores of the patients with diagnosed throat problem related to laryngeal discomfort and of the 40 healthy participants were compared to test the clinical validity (discriminant validity). Also, internal consistency reliability was assessed using Cronbach α coefficient. The relative reliability was calculated by asking 40 of all patients out of the 80 participants, to complete the VHI-Tp twice, with a week of interval between the first and the second times. To detect the absolute reliability, Standard Error of Measurement and Smallest Detected Change were calculated. RESULTS: Discriminative validity differed significantly between patients and healthy participants. There was a significant correlation between the VHI-Tp and Voice Symptom Scale total scores (r = 0.6, P < 0.05). The internal consistency was confirmed (Cronbach α = 0.78). The test-retest reliability was excellent (intraclass correlation coefficient = 0.95).The Standard Error of Measurement and Smallest Detected Changes were acceptable (0.39 and 1.08), respectively. CONCLUSION: The Persian version of the VHI-T was demonstrated to be a valid and reliable self-rated questionnaire for use in Persian patients with throat problem related to laryngeal discomfort.

The Effect of Bimaxillary Orthognathic Surgery on Nasalance, Articulation Errors, and Speech Intelligibility in Skeletal Class III Deformity Patients.

BACKGROUND: We aimed to detect the changes in nasalance, articulation errors, and speech intelligibility after bimaxillary orthognathic surgery in skeletal class III patients. METHODS: This double-blinded before and after quasi-experimental study was conducted in the Department of Maxillofacial Surgery, Qaem Hospital, Mashhad, Iran from Mar 2019 to Apr 2020. The main intervention was maxillary advancement with LeFort I osteotomy and mandibular setback surgery with bilateral sagittal split osteotomy (BSSO). The nasalance score, speech intelligibility, and articulation errors were evaluated one week preoperatively (T0), 1 and 6 months (T1, T2) postoperatively by a speech therapist. The significance level was set at 0.05 using SPSS 21. RESULTS: Eleven women (55%) and 9 men (45%) with a mean age of 31.95 ± 4.72 yr were enrolled. The mean maxillomandibular discrepancy was 6.15 ± 1.53 mm. The mean scores of nasalance for the oral, nasal, and oral-nasal sentences were significantly improved postoperatively (P<0.001). Pre-operative articulation errors of consonants /r/, /z/, /s/ and /sh/ were corrected following the surgery. The percentage of speech intelligibility was significantly increased over time (P<0.001). CONCLUSION: The patients might show a normal articulation pattern and a modified nasalance feature, following maxillary advancement plus mandibular setback surgery.

Voice Changes During Pregnancy Trimesters in Iranian Pregnant Women.

OBJECTIVE: This study aimed to evaluate the vocal changes in the Iranian pregnant women according to trimesters both objectively and subjectively. METHODS: There were 93 pregnant women and 31 non-pregnant women participants in the study. Thirty-three of the 93 pregnant women were in their first trimester, 31 in their second trimester, and 29 in their third trimester of their pregnancies. Clinical data were collected from the acoustic measurements, aerodynamic assessment, video laryngoscopy examination, and the self-assessment of quality of life related to voice using the Persian Voice Handicap Index (VHIP). The analysis of variance (ANOVA) test and Kruskal-Wallis test were used for between-group comparisons of the data. RESULTS: Decreased maximum phonation time (MPT), increased S/Z ratio, increased VHIP-30 scores, and evidence of vocal fold edema were the parameters that differed significantly only in the third trimester. Acoustic analysis revealed that F0, jitter, shimmer, and noise-to-harmonics ratio (NHR) were not significant across the four groups. CONCLUSIONS: Results showed that decreased MPT, increased S/Z ratio, mild to moderate edema, and a deterioration of the VHIP-30 score noticeably occurred during the third trimester. The results suggest significant vocal changes toward less stable phonation during the third trimester of pregnancy.

The Singing Voice Handicap Index (SVHI): Validation and Adaptation Into Persian.

OBJECTIVES: The aim of the present study is to develop, validate, and assess the reliability of the Persian version of Singing Voice Handicap Index (SVHIp) as a self-reported questionnaire for singers with voice disorders that measure the patient's self-perceived voice handicap. STUDY DESIGN: This is a cross-sectional study. MATERIALS AND METHOD: During this study, the Persian version of singing voice handicap index was administered to 115 singers (90 male and 25 female, age range: 22-45 years). Voice disorder was confirmed by video-stroboscopic evidences in 48 participants, while 67 were healthy without any voice disorders. To assess the content validity, the prefinal questions were given to 15 experts to comment on its content applicability and relevance through a Likert scale. Seventy five singers rated its importance to detect face validity. To evaluate the concurrent validity, the same 75 participants completed both the SVHIp as well as a visual analog scale. The SVHI total scores of the singers with diagnosed voice disorder and of the healthy singers were compared to test the clinical validity (discriminant validity). Also, internal consistency reliability was assessed using Cronbach α coefficient. The relative reliability was calculated by asking 40 of all singers to complete the SVHIp twice, with a week of interval between the first and the second times. To detect the absolute reliability, Standard Error of Measurement and Smallest Detected Change were calculated. Responsiveness was measured for the Persian version of SVHI by comparing the individual patient scores before and after the treatment. RESULTS: The SVHI was favorably accepted with no deletions. Discriminative validity differed significantly between singers with and without voice disorder. There was a significant correlation between the SVHIp and visual analog scale total scores (P < 0.05). The internal consistency was confirmed (Cronbach α = 0.78). The test-retest reliability was excellent (intraclass correlation coefficient = 0.95). The Standard Error of Measurement and Smallest Detected values were acceptable (0.39 and 1.08), respectively. The Cohens' d effect size indicates the high responsiveness for SVHIp. CONCLUSIONS: The Persian SVHI was demonstrated to be a valid and reliable self-rated questionnaire for use in Persian-singers.

The Vocal Fold Dysfunction Questionnaire: Validity and Reliability of the Persian Version.

OBJECTIVES: The aim of this study was to develop, validate, and assess the reliability of the Persian version of Vocal Cord Dysfunction Questionnaire (VCDQP). STUDY DESIGN: The study design was cross-sectional or cultural survey. MATERIALS AND METHODS: Forty-four patients with vocal fold dysfunction (VFD) and 40 healthy volunteers were recruited for the study. To assess the content validity, the prefinal questions were given to 15 experts to comment on its essential. Ten patients with VFD rated the importance of VCDQP in detecting face validity. Eighteen of the patients with VFD completed the VCDQ 1 week later for test-retest reliability. To detect absolute reliability, standard error of measurement and smallest detected change were calculated. Concurrent validity was assessed by completing the Persian Chronic Obstructive Pulmonary Disease (COPD) Assessment Test (CAT) by 34 patients with VFD. Discriminant validity was measured from 34 participants. The VCDQ was further validated by administering the questionnaire to 40 healthy volunteers. Validation of the VCDQ as a treatment outcome tool was conducted in 18 patients with VFD using pre- and posttreatment scores. RESULTS: The internal consistency was confirmed (Cronbach α = 0.78). The test-retest reliability was excellent (intraclass correlation coefficient = 0.97). The standard error of measurement and smallest detected change values were acceptable (0.39 and 1.08, respectively). There was a significant correlation between the VCDQP and the CAT total scores (P < 0.05). Discriminative validity was significantly different. The VCDQ scores in patients with VFD before and after treatment was significantly different (P < 0.001). CONCLUSIONS: The VCDQ was cross-culturally adapted to Persian and demonstrated to be a valid and reliable self-administered questionnaire in Persian-speaking population.