farhad torabinezhad

One of the side effects of radiation therapy for non-laryngeal head and neck cancers is laryngeal damage, leading to vocal disorders. Considering the impact of voice on the patient’s quality of life, the long-term follow-up after treatment using a voice handicap index questionnaire is the aim of this study.

This descriptive-analytical study included 30 patients with non-laryngeal head and neck cancers and 30 normal individuals. Specialized examinations have confirmed damage in the larynx. The VHI Questionnaire sub-group scores were assessed at 6 and 24 months post-treatment, along with the voice quality of patients and a control group at 24 months post-treatment. Pearson's correlation coefficient test was used to assess the relationship between each sub-group of the questionnaire at the two mentioned time points.

The patients' examination results revealed a significant decrease in the total questionnaire scores from 19.8 at 6 months to 11.37 at 24 months post-treatment (P < 0.05). The study found no significant difference between the patient and control groups after 24 months (P < 0.05). The questionnaire sub-group scores showed a negative correlation, indicating a trend of decreasing scores at the final follow-up.

This study showed that after the treatment, the radiation damage decreased over time and improved the patient's quality of life.

This research aims to evaluate the validity and reliability of the Persian version of the voice symptom scale (VoiSS) questionnaire. We also sought to determine the best cut-off point to classify high-risk populations into controls (participants) and dysphonic patients. 

The study was conducted in 3 main steps. The translation process was carried out by a pair of Iranian bilingual speech-language pathologists along with an expert panel. For the validity study, the questionnaire was administered to 268 cases that were suspected of dysphonia. Finally, to assess the reliability, the questionnaire was completed twice in 2 weeks by 40 dysphonia patients. To normalize data generation 107 individuals without dysphonia completed the P-VoiSS, after that the cutoff value of the P-VoiSS was calculated.

Cronbach’s α was estimated at 0.914, and for impairment, emotional, and physical domains, it was 0.877, 0.926, and 0.725, respectively. We also estimated intra-cluster correlation (ICC) of 0.984 indicating high reproducibility of the Persian VoiSS questionnaire. The estimated intra-cluster correlation (ICC) for subscale was 0.962 for impairment, 0.989 for emotional, and 0.952 for physical domains. The Mean±SD score of the questionnaire for the healthy group was 10.1±5.9, while it was statistically higher in dysphonia patients (44.1±20.6). The statistical difference was observed in the subscales of the questionnaire between healthy and dysphonia groups (P<0.05). The exploratory factor analysis determined that the Persian VoiSS has three subtest/latent factors like the original form. We also estimate the best cut-point at 20.5. 

The Persian adaptation of VoiSS is a dependable and effective tool that can be utilized for screening high-risk populations.

Laryngeal disorders are a common health problem that affects people of all ages, genders, and races. One of the main symptoms of laryngeal disorders is changes in the voice, which can be used as an indicator for the presence of such disorders. In this paper, we present a data mining approach for using voice as an indicator for laryngeal disorders.

We collected a dataset of voice recordings from individuals with and without laryngeal disorders including 434 people from two clinical centers in Tehran. The dataset was created using a powerful signal processing program and then based on the difference between male and female voice, the dataset was separated into two datasets. Finally, a Deep Neural Network was implemented for modelling using Python programming language and F1-score, Accuracy, Sensitivity, Specificity, and AUC as the model’s evaluation metrics were reported.

Among all the acoustic features, 23 features were selected for the male dataset and 25 features for the female data set. For the male dataset the final model achieved F1-Score of 0.915 and Accuracy of 0.910. For the female dataset the result was 0.884 of F1-Score and 0.896 of Accuracy.

Our results show that machine learning algorithms can accurately classify voice recordings into two groups: individuals with laryngeal disorders and those without. The high accuracy achieved by the algorithms suggests that voice can be used as an objective and automated diagnostic tool for laryngeal disorders. 

Laryngeal damages after chemoradiation therapy (RT) in nonlaryngeal head‑and‑neck cancers (HNCs) can cause voice disorders and finally reduce the patient’s quality of life (QOL). The aim of this study was to evaluate voice and predict laryngeal damages using statistical binary logistic regression (BLR) models in patients with nonlaryngeal HNCs.

This cross‑section experimental study was performed on seventy patients (46 males, 24 females) with an average age of 50.43 ± 16.54 years, with nonlaryngeal HNCs and eighty individuals with assumed normal voices. Subjective and objective voice assessment was carried out in three stages including before, at the end, and 6 months after treatment. Eventually, the Enter method of the BLR was used to measure the odds ratio of independent variables.

In objective evaluation, the acoustic parameters except for F0 increased significantly (P < 0.001) at the end treatment stage and decreased 6 months after treatment. The same trend can be seen in the subjective evaluations, whereas none of the values returned to pretreatment levels. Statistical models of BLR showed that chemotherapy (P < 0.05), mean laryngeal dose (P < 0.05), V50 Gy (P = 0.002), and gender (P = 0.008) had the greatest effect on incidence laryngeal damages. The model based on acoustic analysis had the highest percentage accuracy of 84.3%, sensitivity of 87.2%, and the area under the curve of 0.927.

Voice evaluation and the use of BLR models to determine important factors were the optimum methods to reduce laryngeal damages and maintain the patient’s QOL.

The present study examined the relationship between the total score of the voice handicap index (VHI) and the total score and scores of the three factors of the vocal fatigue index (VFI) with the medical history of Melli bank workers working in Tehran and Kurdistan privences.

The research is a descriptive-analytical cross-sectional study that was conducted on 444 clerks of Melli Bank branches in Iran (76% male and 24% female with a mean age of 42.3). A demographic questionnaire, the medical history checklist, and the Persian version of VHI and VFI were used to collect data.

The voice handicap index had a significant relationship with a history of neurological (P=0.030) and head and neck (P=0.048) disorders, speech and language disorders (P=0.001), and reflux (P=0.041). Regarding vocal fatigue index, the total score had a significant relationship with head and neck (P=0.006) and speech and language disorders (P<0.001); the first factor with diseases of the head and neck (P=0.018), pharynx and larynx (P=0.005) and speech and language disorders (P=0.001), the second factor with neurological (P=0.020), head and neck (P=0.006), and speech and language disorders (P<0.001), and allergies (P=0.032), and finally, the third factor with neurological (0.044), pharynx and larynx (P=0.031), speech and language disorders (P=0.044), and reflux (P=0.021).

Regardless of the respiratory system, suffering from diseases of the speech and language system can have a significant effect on the scores of the VHI and VFI indices. Meanwhile, the history of speech and language problems and head and neck disorders affect the total score of most factors of the VFI.

Auditory perceptual assessment is one of the important evaluations for voice assessment. Among the available auditory-perceptual assessments, the grade, roughness, breathiness, asthenia, strain (GRBAS) auditory perceptual scale has attracted the attention of many researchers and therapists in Iran and other parts of the world. The GRBAS scale is a perceptual voice assessment scale that subjectively assesses voice quality; however, the audio samples in the original GRBAS scale that are used as training tools for raters are Japanese. There are various segmental and suprasegmental differences between the Japanese and Persian languages since these factors can affect the accuracy of the perceptual evaluation. 

This research aims to investigate the inter-rater agreement among the Persian raters who only had access to the Japanese samples in the main profile.

In this study, 8 speech and language pathologists were selected as raters with more than 5 years of clinical experience in evaluating and treating voice disorders. Several 137 audio samples, containing the prolongation of vowel /a/ and reading the standard text “Grandfather Passage” were provided to the participating raters. The raters were asked to score the audio samples based on the GRBAS auditory perceptual scale. The results were statistically analyzed via the Cohen kappa coefficient.

The highest agreement in the R parameter was related to rater number 5 (kappa=0.585) while the lowest value was related to parameter S, related to rater number 1 (kappa=-0.018).

According to the results, the clinical experience of raters using the Japanese samples cannot lead to an increase in the agreement and ability of Persian-speaking raters in evaluating Persian samples.

Voice assessment is one of the five universal parameters in assessing the speech ability of children with cleft palate. One of the characteristics of cleft palate children is the production of compensatory errors. This study aims to compare the acoustic characteristics of the voice, including fundamental frequency, jitter, shimmer, and average harmonic to noise ratio in cleft palate children compared to their normal peers.

A total of 38 children in the age range of 48 to 60 months (17 children with cleft palate and 21 normal peers) participated in this descriptive-analytical and cross-sectional study. The children were asked to produce sustained vowels /a/ and /i/ while their speech samples were being recorded. The acoustic characteristics of the children’s voices were analyzed via the Praat software.

There were no statistically significant differences in acoustic parameters between the cleft palate children with and without compensatory errors. There were significant differences between children with cleft palate compared to their normal peers in the jitter averages of the vowel /a/ (P=0.05). The gender differences were found in the harmonic to noise ratio averages of the vowel /a/ between children with cleft palate (P=0.02).

Young children with velopharyngeal insufficiency may be at risk of voice problems.

The singing voice handicap index (SVHI) was developed to assess voice-related handicaps in singers.

The purpose of this study was to evaluate the validity and reliability of a Persian translation of the SVHI (P-SVHI) for traditional Persian singers.

A cross-sectional study was performed to translate and validate the P-SVHI using a "forward-backward" procedure. The questionnaire was administered to 275 traditional Persian singers (168 with a normal voice and 107 with dysphonia) ranging from 16 to 83 years. Content, construct, discriminant, convergent, and face validity, test-retest reliability, internal consistency, and floor and ceiling effects were assessed.

The 36-item SVHI, translated from the original English by two translators, was completed by 21 traditional Persian singers. After the face validity was approved, construct validity assessment using factor analysis identified four factors in the P-SVHI with the exclusion of seven items. The mean score of the 29-item P-SVHI on a 0 - 100 scale was 16.9 for healthy subjects and 40.9 for dysphonic subjects. Discriminant validity confirmed that P-SVHI scores were significantly different between normal and dysphonic singers, using an independent sample t-test (P < 0.001). Convergent validity was proven by strong correlations between P-SVHI scores and the Iowa Patient’s Voice Index (IPVI1, IPVI2, and "IPVI effort" scores of r = 0.58, 0.69, and 0.42, respectively, P < 0.001). Internal consistency and test-retest reliability were also excellent (Cronbach α = 0.95, average inter-item correlation = 0.40, and intra-class correlation coefficients using two-way random model with absolute agreement, ICCtwo-way random, absolute agreement = 0.69 - 0.95). No floor or ceiling effects were observed.

The revised 29-item P-SVHI is a valid and reliable tool in differentiating normal and dysphonic Persian traditional singers.

Voice is influenced by personality. However, it is still questionable which acoustic features are influenced by personality traits. This study aimed to investigate the relationship between acoustic characteristics and personality dimensions.

Thirty-three participants with dysphonia and 33 participants without dysphonia were recruited to take part in this cross-sectional study. Personality dimensions were evaluated by the revised NEO personality inventory, and acoustic characteristics by using the Praat software. The tasks included prolongation of the vowel /a/, expression of declarative and interrogative sentences, reading, and connected speech. The acoustic features included fundamental frequency range, jitter, shimmer, harmonic-to-noise ratio, intensity, and duration. SPSS V. 23 was used for statistical analysis. For correlation analysis, the Pearson and Spearman correlation coefficients were employed.

In individuals with dysphonia, a significant relationship was observed between personality dimensions and the following acoustic features: A. extraversion and intensity in connected speech (P=0.045) and the reading task (P=0.036); B. openness and shimmer in /a/ vowel prolongation (P=0.003); C. openness and the harmonic-to-noise ratio in /a/ the vowel prolongation task (P=0.017); and D. agreeableness and duration in expressing interrogative sentences (P=0.019).

In Persian-speaking participants with and without dysphonia, some acoustic characteristics were significantly correlated with the mean score of the personality test (revised NEO personality inventory). It seems that each voice feature is influenced by personality dimensions. This finding indicates that changes in acoustic characteristics of voice due to personality can be evaluated in laboratory and hearing examinations.

Intonation is one of the main aspects of speech prosody, which plays an important role in speech intelligibility. Previous studies have shown that the expression of intonation in children with cochlear implant is the most difficult feature of speech prosody. Regarding the importance of intonation in emotional transmission, sentence type, and communication intentions, the aim of the present study was to examine the speech intonation in cochlear implant and normal hearing children in the imitation and reading tasks.

The present descriptive-analytic study was performed on 30 cochlear implant children versus 30 normal-hearing children. The sound was recorded in a quiet room. The participant was asked to utter the sentence “/dare baroun miyad/” in the happiness mood. Then, they were asked to do the same task imitating from the sound which had been recorded earlier. Data recording was done using Praat software and data analysis was done using SPSS software.

The mean of fundamental frequency for the two groups in reading (P=0.004) and imitation (P=0.007), duration in reading (P=<0.001), and imitation (P=0.003) and intensity of the two groups in reading (P=0.01) had a significant difference. Meanwhile, the longest duration was related to the cochlear implantation group and the highest fundamental frequency and intensity was related to the normal group.

Intonation is one of the damaged aspects of speech in children with cochlear implantation, which results in children’s inability to translate emotions verbally. According to the present study, these children's intonation was damaged in imitation and reading tasks. Therefore, it is recommended that, in addition to the segmental aspect of speech, therapists carry out interventions on the speech intonation of these children.

Patients with muscle tension dysphonia (MTD) suffer from several physical discomforts in their vocal tract. However, few studies have examined the effects of voice therapy (VT) on the vocal tract discomfort (VTD) in patients with voice disorders. Therefore, the aim of the present study was to investigate the effects of VT on the VTD in patients with MTD.   This study was carried out on 25 subjects with MTD, including 5 men and 20 women, with the mean age of 37.20±5.70 years. The participants underwent 10 consecutive sessions of VT twice a week. The acoustic voice analysis, auditory-perceptual assessment, and the Persian version of the vocal tract discomfort (VTDp) scale were used to compare the pre- and post-treatment results.   After VT, significant improvements were observed in the acoustic characteristics, including jitter, shimmer, and harmonics-to-noise ratio (P<0.05). Regarding the auditory-perceptual assessment, a significant reduction was noticed in the overall severity, roughness, and breathiness (P<0.05). Moreover, VT led to a significant reduction in all the items of the VTDp, including burn, tightness, dryness, pain, tickling, soreness, irritability, and lump in the throat, after VT in both frequency and severity sections of the VTDp scale (P<0.05).   The results of the present study showed that VT can be effective in reducing the frequency and severity of the VTD in patients with MTD in addition to improving voice quality.

Vocal abuse and misuse would result in vocal fold polyp. Certain features define the extent of vocal folds polyp effects on voice acoustic parameters. The present study aimed to define the effects of polyp size on acoustic voice parameters, and compare these parameters in hemorrhagic and non-hemorrhagic polyps.
In the present retrospective study, 28 individuals with hemorrhagic or non-hemorrhagic polyps of the true vocal folds were recruited to investigate acoustic voice parameters of vowel/ æ/ computed by the Praat software. The data were analyzed using the SPSS software, version 17.0. According to the type and size of polyps, mean acoustic differences and correlations were analyzed by the statistical t test and Pearson correlation test, respectively; with significance level below 0.05.
The results indicated that jitter and the harmonics-to-noise ratio had a significant positive and negative correlation with the polyp size (P=0.01), respectively. In addition, both mentioned parameters were significantly different between the two types of the investigated polyps.
Both the type and size of polyps have effects on acoustic voice characteristics. In the present study, a novel method to measure polyp size was introduced. Further confirmation of this method as a tool to compare polyp sizes requires additional investigations.

In children's speech disorders, assessing the percentage index of speech intelligibility is important. Expression of single words and sentences in some ways, such as the effect of voices on eachother, is different, that may affect speech intelligibility. In the present study, attempts were made to answer the question whether the percentages of speech intelligibility are different in these two tests.

In the present cross-sectional study, 120 healthy children (60 girls and 60 boys) were chosen among all kindergartens in Ghaemshahr city, Iran. Children's speech samples were collected by means of calling pictures and repeating sentences. The voices were tape-recorded and children's speech intelligibility was studied in four age groups within six months. Comparison of the intelligibility of the two speech samples was carried out using Wilcoxon Tests and the correlation between children’s scores in the expression of words and sentences was determined using Spearman correlation.

The mean score of the speech intelligibility was 94% (SD=10.66) in the words test and 96/02% (SD=9.65) in the sentence test. A significant difference was observed between age groups in both tests (α =0/05). Also, there was a significant correlation between the intelligibility of words and sentences (p=0.000). However, no statistically significant difference was found between boys and girls.

The significant difference found in the speech intelligibility percentages of words and sentence test shows that language and communication factors affecting the listener's understanding of other's speech are different. So, in measuring the speech intelligibility using these two tests, we should not expect similar results. Increase in the speech intelligibility percentage in sentence test may be due to the abundance of semantic clues, which can increase the listener's guessing capability.

Excessive duration is one of the suprasegmental features in cochlear implant children. Regarding the importance of the normal rate of speech in transferring the intonation and clarity of speech, the present study aims at comparing word and sentence duration in cochlear implant and normal hearing children in imitation and reading tasks.

The present descriptive-analytical study was performed on 30 elementary school cochlear implant children versus 30 normal hearing children. Voice recording was done in a silent room. The Persian-speaking subject was asked to utter “/sælam/ (hello)” and “/Ɂemruz nemiyad/ (He won’t come today)” with the following moods and emotions: statement, question, exclamation, with happiness and with sadness. Then, they were asked to do the same task imitating the voice which had been recorded earlier. Data recording was done using Praat software and data analysis was done by SPSS software.

The average duration in cochlear implant children in two modes of imitating and reading a word showed a significant difference with that of children with normal hearing (P < 0.001). Moreover, in both groups, the average duration of reading the word was less in comparison with imitating the word. Also, the average duration in cochlear implant children in two modes of imitating and reading a sentence showed a significant difference with that of children with normal hearing (P< 0.001). In the cochlear implant group, the average duration of imitating the sentence was less than the average duration of reading the sentence, whereas in the normal hearing group, the average duration of reading the sentence was less than the average duration of imitating the sentence.

The average duration in cochlear implant in all modes (word imitation, word reading, sentence imitation, sentence reading) was more than normal hearing children, which results in abnormal intonation in these children. According to the present study, imitation cannot cause a decrease in duration and consequently, does not result in more natural intonation. Hence, it is probably not a proper therapeutic method.

Repeated efforts by researchers to impose voice changes by laryngeal surface electrical stimulation (SES) have come to no avail. This present pre-experimental study employed a novel method for SES application so as to evoke the motor potential of the internal superior laryngeal nerve (ISLN) and create voice changes.
Thirty-two normal individuals (22 females and 10 males) participated in this study. The subjects were selected from the students of Iran University of Medical Sciences in 2014. Two monopolar active electrodes were placed on the thyrohyoid space at the location of the ISLN entrance to the larynx and 1 dispersive electrode was positioned on the back of the neck. A current with special programmed parameters was applied to stimulate the ISLN via the active electrodes and simultaneously the resultant acoustic changes were evaluated. All the means of the acoustic parameters during SES and rest periods were compared using the paired t-test.
The findings indicated significant changes (P=0.00) in most of the acoustic parameters during SES presentation compared to them at rest. The mean of fundamental frequency standard deviation (SD F0) at rest was 1.54 (SD=0.55) versus 4.15 (SD=3.00) for the SES period. The other investigated parameters comprised fundamental frequency (F0), minimum F0, jitter, shimmer, harmonic-to-noise ratio (HNR), mean intensity, and minimum intensity.
These findings demonstrated significant changes in most of the important acoustic features, suggesting that the stimulation of the ISLN via SES could induce motor changes in the vocal folds. The clinical applicability of the method utilized in the current study in patients with vocal fold paralysis requires further research.

As the most perceived and articulated errors of hearing aid users occur in high frequency speech phonemes, this study aimed to find a way to amplify and reconstruct the errors. Thus, the study first prepared a recorded form of two Persian fricative consonants as stimulus; then, the rate of the prescribed gain of the two methods of National Acoustic Laboratories-Nonlinear 2 (NAL-NL2) and the Desired Sensation Level Multistage Input/Output (DSLm[i/o]) were compared. This study was performed using eight programmed hearing aids for severe sensorineural hearing loss in three configurations: flat, raising, and sloping. After fitting the hearing aids upon the NAL-NL2 and DSLm[i/o] methods, the rate of their gain for the consonants of /s/ and /f/, using Affinity 2.0 analyzer, was determined in 2 cc coupler at the three different levels. In the flat and raising audiograms, the prescribed gain of DSLm[i/o] for the two consonants in all three speakers and intensity level was more than NAL-NL2 (p<0.05). In the sloping audiogram, the significance of the difference of prescribed gain of these methods disappeared; however, the DSL m[i/o] in the low frequency area was higher than NAL-NL2 (p<0.001). The average prescribed gain of methods in the three frequency regions for the two consonants is different, and the prescribed gain of DSLm[i/o] in all frequencies, especially in the low frequency areas, is higher than NAL-NL2.

Velopharyngeal coarticulation refers to the influence of a nasal consonant on preceding segments or the following segments during continuous speech. Coupling of the nasal resonating space to the oropharyngeal cavity alters the vocal tract formants in complex ways. The purpose of this study was to investigate the effect of nasal coarticulation and /a/ vowel frequency formants in cleft palate Persian speaking children. In present cross-sectional study, voice samples of 30 cleft palate children ranging 4-12 years were investigated. Participants were asked to repeat /ama/ three times and vowel /a/ after presentation of an auditory model. Afterwards, obtained samples were analyzed using Praat (version 5.3.13) software. Investigating the effect of nasalization on formants of /a/ vowel before and after nasal consonant and comparing with single prolonged /a/, “Bi-variate analysis of variance test” were used. There were no significant differences of fundamental frequency (F0) between /a/ which proceeds nasal consonant and /a/ follows nasal consonant, the before nasal consonant /a/ versus single /a/ and the after nasal consonant /a/ versus single /a/ in normal and cleft palate children (P>0.05). However, findings revealed statistically significant differences of first, second and third formants (F1, F2, F3) between three situations (p<0.001). In the cleft palate children, F1, F2, F3 in /a/ before nasal consonant affected by anticipatory nasal coarticulation and in /a/ after nasal consonant affected by carry-over nasal coarticulation. This study showed nasal coarticulation and nasalization result in decreasing F1, F2, F3 in /a/ vowel.

Nasalization of a vowel refers to the addition of nasal resonance to the vocal tract transfer function. Also، vowel nasalization occurs because of coarticulation. Coupling of the nasal resonating space to the oropharyngeal cavity alters the vocal tract formants in complex ways. The purpose of this study was to investigate the effect of nasalization on /a/ vowel formants in before and after nasal consonant. In current cross-sectional study، voice samples of 60 normal children ranging the age of four-nine years were investigated. Participants were asked to repeat / ʔ ama/ three times and vowel /a/ after presentation of an auditory model. Then، obtained samples were analyzed using Praat 5. 3. 13. Average of F0، F1، F2 and F3 were calculated for /a/ comes before and after /m/ in production of / ʔ ama/ over three trials. There were statistically significant differences of F1، F2 and F3 between / a/ which proceeds nasal consonant and /a/ follows nasal consonant، the before nasal consonant /a/ versus single /a/ and the after nasal consonant /a/ versus single /a/ (p=0. 001 for all). F1، F2 and F3 in /a/ before nasal consonant affected by anticipatory nasal coarticulation and in /a/ after nasal consonant affected by carry-over nasal coarticulation. This study showed nasal coarticulation and nasalization result in decreasing F1، F2 and F3 in /a/ vowel.

Voice disorders assess with the help of laboratory equipments and perceptual evaluation. Voice samples involve vowel prolongation, text-reading or conversational speech. In Iran, Rainbow text and Grandfather text, were developed for assessing voice. This study was cross-sectional and descriptive-analytical. Mean and fundamental frequency variations range in 120 normal males and females aging from 20-59 years old were studied. Voice samples of reading both texts were gathered and compared. Mean fundamental frequency in males in Grandfather text was 137.93 with SD 1.2 and in Rainbow text was 135.09 with SD 1.1 (p>0.05), in females Grandfather and Rainbow texts were 206.07 with SD 0.9 and 204.23 with SD 2.1, respectively (p>0.05). Fundamental frequency variations range in Grandfather text in males was 88.10 with SD 0.8 and in females was 116.77 with SD 1.3 and in Rainbow text in males was 90.92 with SD 1.1, in females was 116.08 with SD 1.2 (p>0.05). Mean fundamental frequency of males in each text didnt show significant difference in age groups and just in 50-59 age group of the female population showed significant difference. Fundamental frequency variations range didnt show significant difference in males and females in both texts. These two texts were the same in measurement of average and fundamental frequency variations range in adults. Significant difference showed between 50-59 age group of the female population and other groups.

prosody is a very important factor in communication and includes such parameters as: duration, intonation, pitch, stress, rhythm etc. Intonation is the pitch variation in one sentence. Duration is the time taken to utter a voice. The aim of the present study was to evaluate some parameters of prosody such as duration and intonation curve in interrogative sentences among normal Farsi speaking adults in order to determine the characteristics of this aspect of language with an emphasis on laboratory testing. This study was performed as a cross-sectional one. The participants included 134 male and female Farsi speaking individuals aging between 18-30 years. In this study two interrogative sentences with open and closed answers were used. The voice samples were analyzed by Dr.speech -real analysis software. Data analysis incorporated unilateral analysis of variance and an intonation curve was drawn for each sentence. The parameter of duration among men and women was significantly different (p≤0.001). Duration in open questions was significantly longer than yes/no questions (p≤0.001). The intonation curve of the two groups were similar. Men and women use duration changes, for making difference in prosody. On the whole, duration among women is longer than men. In open questions, the duration of sentences is mostly due to the question word. The intonation curve in open questions has more amplitude. Women show much more changes in basic frequency for transferring interrogative state in their expressions.

Formant structure and vowel space are the most important acoustic characteristics of speech sounds. The purpose of this study was to determine formant frequency and vowel space in six Persian vowels. This cross-sectional descriptive-analytic study was performed on 60 Persian students of Tehran University of Medical Sciences (30 males, 30 females) with their age ranging from 18 to 24 years. The subject articulated six Persian vowels in isolation and data was recorded by real-analyzer software. Then, the first three formant frequency of each vowel was determined for each subject. Vowel formant frequency averages were measured separately for each vowel and each gender. Vowel space was plotted. The difference between F0 in two groups was compared by Leven and independent sample t tests. Maximum and minimum values of F0 in both group was related to /æ/ and /a/ (135 Hz in males and 239 Hz in females) and /i/ (146 Hz in males and 239 Hz in females). Besides, F0 in females was significantly higher than males (p<0.001). Maximum and minimum values of F1 were related to /æ/ and /i/. Furthermore, maximum and minimum values of F2 were related to /i/ and /u/. Maximum and minimum values of F3 were related to /i/ and /u/. The lowest vowels were /æ/ and /a/ and the highest was /i/. The frontest was /i/ and the backest was /u/. the spreadest vowel was /i/ and the roundest was /u/.

Speech intelligibility is defined as a measure of effectiveness of understanding speech. It has many applications such as nomination of speech disorder intensity. Different methods and speech tasks have been designed for assessment of speech intelligibility amongst which word identification tasks have high validity. This study aimed to provide a test to measure speech intelligibility among children aged 3 to 5 years old. Many words were collected and content validity was assessed by 9 speech-language pathologists and 1 linguist. Thirty four words with a content validity above 70% were chosen as the test words and the speech-language pathologists collected suitable pictures for the words. One hundred boys and girls aged 3 to 5 years participated in the study. Inter-rater reliability was administered to assess the test reliability. An interclass correlation coefficient of 0.85 and spearman correlation coefficient of 0.81 was obtained for the speech intelligibility test. Speech intelligibility test has appropriate validity and reliability and is suitable for assessment of intelligibility in 3 to 5 years old children.

ob Nasality is one of the important parameters in pathology of voice resonance. Voice of normal adults has nasality to some extend. It appears that nasality, like other parameters of voice, can be affected by loudness which can be measured in experimental evaluations. This study was conducted to determine the effect of vocal loudness on nasalance of vowels in normal adults and to identify the relationship between these two factors in 18-28 year-old normal Persian-speaking adults. In this descriptive-analytic and cross sectional study, sample voices of 65 randomly selected male and female 18 to 28 year-old normal Persian-speaking students of Rehabilitation College in Iran Medical Sciences University were studied. Mean of Nasalance in Persian vowels was computed with Nasal View software. The findings were analyzed with descriptive statistical analysis and one-way ANOVA. Maximum nasalance was in low voice and minimum nasalance was in loud voice in both men and women subjects. The statistical results show that nasalance in 3 levels of low, normal, and loud voices have significant differences (p < 0.05). In normal adults, vowel nasalance is decreased with increase in vocal loudness. This is an aspect of normal speech mechanism. The findings can be explained considering function of velopharengeal port, raise in subglottal air pressure in loud voice, and increased muscle contraction of pharynx and palate.

Reflux laryngitis is extremely common among patients with voice disorder. Medical therapy approaches are not efficient enough. The main goal of this study is to assess the acoustic and laryngeal characteristics of patients with dysphonia before and after medical or voice therapy, and to evaluate the effectiveness of each.

In this retrospective study, 16 reflux laryngitis patients were assessed. Five received complete voice therapy, tow ceased voice therapy and nine received medication. Perceptual voice evaluation was performed by a speech-language pathologist, the severity of voice problem was calculated, based on the affected acoustic and laryngeal characteristics pre- and post-treatment.

Post-treatment evaluation in patients who received complete voice therapy indicates 80 percent improvement in the severity of disorder and 100 percent improvement in the perceptual voice evaluation. After medical therapy, we observed that voice disorder and perceptual voice evaluation are improved 44 and 66 percent respectively. The improvement was statistically significant in both treatment approaches: complete voice therapy (P=0.039) and medical therapy (p=0.017).

In patients with reflux laryngitis, most acoustic and laryngeal characteristics were normal and satisfying after the treatment. It can be concluded that the proficiency of voice therapy in improving the acoustic and laryngeal characteristics is comparable to medical therapy.