Background and Aim: Human’s voice is observable and measurable like his other behaviours. Investigations have shown that characteristics of voice differ in males and females and possibly in different languages. Clinically, knowing natural voice characteristics is helpful for distinguishing voice pathologies. So the purpose of this study was to measure and compare the fundamental frequency human voice.

Materials and Methods: subjects were young males and females of Iranian Fars, Turk and Kurd races. First the subjects were asked to read some Persian sentences , then their voice samples were analysed by Dr.Speech software.

Results: Fundamental frequency mean is 168±46 Hz and 120±48 Hz for females and males , respectively , which shows significant difference. There is no significant difference between fundamental frequency mean of different races.

Conclusion: There is significant difference between fundamental frequency of males and females , but this difference is not attributable to their mother tongue. Key words: voice, fundamental frequency, Iranian, Fars , Turk , Kurd.

Background and Aim: Objective measurement is general and acoustic measurements in particular have become a substantial aspect of stuttering assessment during the last few decades. Measurements do not replace the perceptual judgment, but they allow a more precise diagnosis, provide more evidence for therapeutic interventions, and are useful as feedback for patients in therapy. The purpose of this investigation was to compare some adult male stutterers&apos and nonstutterers&apos acoustic features.
Materials and Methods: Adult male stutterers and nonstutterers participated this case-control  study. Their fluent reading of 20 sentences in Farsi, prolongation of  vowels /a/ and /i/, and rhythmic counting from 1 to 20 were analyed with Dr. Speech software.
Results: There were no significant differences between two groups in fundamental frequency (f₀) and standard deviation of f₀ in three speech samples (vowels /a/ and /i/, reading 20 sentences, and rhythmic counting from 1 to 20). No significant difference were between two groups for jitter and shimmer.
Conclusion: Non significant differences between two groups are somewhat due to investigation of this parameters in fluent speech of stutterers  and nonstutterers.

Background and Aim: In recent years, several tools for assessment of quality of patient life have been designed especially for dysphonics. Nowadays, we have useful assessments in health system that are refered for numerous clinical decisions. In this way, this investigation compares clinician and patient perception in dysphonic and normal voiced for first time.

Methods: This study was carried out on 30 dysphonic and 30 subjects with normal voice. Their age, sex and job were same. In two groups, Consensus Auditory - Perceptual Evaluation of Voice (CAPE-V) was used for evaluation of clinician perception and Voice Handicap Index - 30 (VHI-30) for assessment of patient perception. After collecting data, they were analyzed by Mann- witney and Wilcoxon tests.

Results: The research revealed that mean of total and each section score of VHI-30 have significant difference between dysphonic and control group (p<0.01). Comparison of total and every parameter score of CAPE-V and speed also indicated significant difference between two groups (p<0.01). Study of reliability shows weak reliability (r=0.34) between clinician and patient perception of voice in dysphonics.

Conclusion: Dysphonic patients percept their voice problem different and severe rather than clinicians that shows physical, psychological and social affects of dysphonia. This research confirms that patient - based assessment of voice is necessary to be part of common assessments of dysphonia.

Background and Aim: Hearing has an important role in speech production and making phonological distinction, especially voicing distinction. Voice onset time (VOT) has been a reliable acoustic cue of voicing differences in plosive consonants. The purpose of this study was to measure VOT in initial Persian (Farsi) oral plosives produced by cochlear implanted children, comparing to normal hearing children.
Methods: In this cross-sectional study, 20 cases and 20 controls were assessed. Cases were prelingually deaf children who were cochlear implanted 4.5 years prior to test. Controls were normal hearing children at 4.5 years of age. VOT were measured while children uttered oral plosives. The effect of hearing status, voicing, and gender on VOT were assessed.
Results: The amount of VOT of plosives produced by girls was higher than boys, in both groups. This difference was significantly higher in voiceless plosives than in voiced ones. In both groups, voiceless plosives had long-positive VOT value while the amount of VOT was short-positive regarding voiced plosives.
Conclusion: It was demonstrated that VOT is significantly correlated with voicing. In voiceless plosives, VOT could not be considered as a phonetic correlate of hearing status whereas it made significant differences between cochlear implanted children and hearing controls. Furthermore, it was confirmed that concerning voiceless plosives, the amount of VOT of girls was significantly higher than boys. On the contrary, in voiced plosives, gender had no significant effect on the amount of VOT.

Background and Aim: Vocal abuse and misuse are the most frequent causes of voice disorders. Consequently some therapy is needed to stop or modify such behaviors. This research was performed to study the effectiveness of vocal hygiene program on perceptual signs of voice in people with dysphonia.
Methods: A Vocal hygiene program was performed to 8 adults with dysphonia for 6 weeks. At first, Consensus Auditory- Perceptual Evaluation of Voice was used to assess perceptual signs. Then the program was delivered, Individuals were followed in second and forth weeks visits. In the last session, perceptual assessment was performed and individuals&apos opinions were collected. Perceptual findings were compared before and after the therapy.
Results: After the program, mean score of perceptual assessment decreased. Mean score of every perceptual sign revealed significant difference before and after the therapy (p≤0.0001). «Loudness» had maximum score and coordination between speech and respiration indicated minimum score. All participants confirmed efficiency of the therapy.
Conclusion: The vocal hygiene program improves all perceptual signs of voice although not equally. This deduction is confirmed by both clinician-based and patient-based assessments. As a result, vocal hygiene program is necessary for a comprehensive voice therapy but is not solely effective to resolve all voice problems.

Background and Aim: 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.
Methods: 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.
Results: 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).
Conclusion: 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.

Background and Aim: The voice of human being changes during lifetime with different patterns in males and females. In addition to assessment of changes due to aging, some studies examined the voice changes among various languages and ethnical groups. This study is performed to evaluate the fundamental frequency changes in normal 9-50 year-old Persian (Farsi) speaking individuals.
Methods: In this cross-sectional study, 320 voice samples in normal voiceless environment were recorded. The mean of fundamental frequency of vowels and counting is measured by Dr Speech software (real analysis program). Data analysis was performed by MANOVA test and the profiles of their changes were plotted.
Results: The profile of mean of fundamental frequency changes was different in males and females. The mean of fundamental frequency was equal in both genders until 13 years old and the samples of voice had low pitch (Mean: higher than 200 Hz). MFF after 13 years old significantly decreased in males specially in vowels (p<0.001). The changes in vowels and counting were similar. The mean of fundamental frequency in both genders, between 20-40 years old had  relative constancy.
Conclusion: The mean of fundamental frequency changes of vowels and counting in females and males result from diverse dimensions of larynx and other anatomical differences. Significant changes of mean of fundamental frequency in both genders after 13 years old result from puberty in males. The proportional consistence of mean of fundamental frequency between 20-40 years old is probably due to the uniformity of body in this age range.

Background and Aim: Glottic closure pattern is one of the most important stroboscopic signs in judging the normality of laryngeal function. According to the recent researches, complete glottic closure is not the only pattern in normal phonation. The aim of this study was to investigate the glottic closure pattern in normal subjects and to understand the role of sex in having different glottic closure patterns.
Methods: In a cross-sectional study, 80 subjects (58 females and 22 males mean age of 21.19 years) were randomly selected from a population of 218 students. After taking a full medical history and performing perceptual and voice self assessment, subjects without any vocal disorders were recruited. Videolaryngoscopic assessment was performed during producing the vowel sound /i/ in habitual, high, low, loud and soft levels of phonation. Glottic closure patterns were analyzed in different phonation and also were compared between males and females.
Results: Although complete closure was the most frequent pattern, Y posterior chink was the second pattern in males (20.2%) and females (39.4%) in all phonation. The results revealed significant difference between males and females in glottic closure pattern (p=0.001). Moreover, significant differences were observed in habitual (p=0.004), high (p=0.006) and soft (p=0.02) phonations between males and females however, the differences in low (p=0.7) and loud (p=0.19) phonations between males and females were not significant.
Conclusion: Y posterior chink, as well as complete closure, are likely to be normal findings in people with normal voice. Besides, gender has a significant influence on glottic closure pattern.

Background and Aim: Vocal cord nodule is one of the voice disorders causes hoarseness and breathy voice. Voice therapy is one of the treatment approaches. We aimed to find out the effects of voice therapy on vocal acoustic characteristics in these patients.
Methods: In this case series, five women with vocal nodule (14 to 45-year-old) participated in a 9-week voice therapy program developed by Boone. Vocal hygiene and voice practices were measured every day using a questionnaire. Moreover, structure and movements of vocal folds were examined using videolaryngostroboscope by a laryngologist before and after voice therapy to evaluate the effectiveness of program. For collecting voice samples we used sustained /æ/ in comfortable loudness for all patients and data were analyzed using Speech Studio.
Results: After voice therapy, fundamental frequency in four of five subjects were decreased but it was not significant (p=0.225). However, jitter in all of five subjects was significantly decreased (p=0.043). After voice therapy, shimmer in three of five subjects were decreased that was not significant (p=0.345).
Conclusion: Voice therapy can be used for the remedy of acoustic vocal characteristics and elimination or contraction of vocal cord nodule.

Background and Aim: 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.
Methods: 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.
Results: 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 didn&apost show significant difference in age groups and just in 50-59 age group of the female population showed significant difference. Fundamental frequency variations range didn&apost show significant difference in males and females in both texts.
Conclusion: 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.

Background and Aim: Evaluation of voice problem involves perceptual, acoustic, aerodynamic and physiological measure. In recent years assessment of patients point of view use as a essential part of evaluation. The aim of this study was construct a questionnaire for assessment of physical, functional and emotional voice problems in adults.
Methods: This study is a kind of constructing battery. Based on a comprehensive study of many foreign questionnaires, "The voice symptoms assessment" questionnaire in adult was produced. Its content validity was determined according to the judgment of 7 speech and language pathologists. This questionnaire administered to 60 voice patients (20 female and 40 male) between 18 to 60 years old that could read and write in Persian. The reliability of this questionnaire is determined by the method of Cronbach Alpha and split half.
Results: Content validity index of this questionnaire was 0.94. Cronbach Alpha was high (more than 0.7) and Spearman-Brown coefficient of split half was 0.96. Correlatoin Coefficient was statistically significant between 3 parts and total questionnaire (p<0.01).
Conclusion: "The voice symptoms assessment" questionnaire in adult has good content validity and reliability and reflects the wide range of physical, functional and emotional problems in voice patients. This questionnaire is simple for patients to complete and easy to score. It seems that use of this questionnaire, as part of a complete voice evaluation will be helpful in future.

Background and Aim: An imbalance between phonatory subsystems may lead to disturbing phonatory muscular balance and consequently voice disorders. Based on theoretical issues, criterion-based laryngeal manual therapy, as a novel treatment method which is supported by classical laryngeal manual therapy, can improve voice quality using manual maneuvers combined with phonatory tasks. The present study aimed to report the treating effects of this method on hyperfunctional voice disorders.

Methods: Twenty adult participants with hyperfunctional voice disorders by the least three months history of voice disorder were selected. The participant’s voices were assessed multidimensionally using acoustic, audio-pecreptual and stroboscopic assessments before and after treatment.

Results: There were a decrease in jitter (p=0.003) and shimmer (p<0.001) and also, increase in harmonic-to-noise ratio (HNR) (p<0.001) of vowel /a/ after treatment. Besides, there was an increase in harmony to noise ratio (p=0.009) and decrease in jitter (p=0.020) of vowel /i/, too. There were not significant changes in shimmer amount of vowel /i/ (p=0.170) after treatment. There were highly significant changes in all aspects of audio-perceptual (p<0.001) and videostroboscopic (p<0.001) parameters.

Background and Aim: Teachers are a large group of professional voice users that several risk factors and voice demands causes various voice complaints among them. As the voice is multidimensional, the aim of this study was acoustic and perceptual measurement of teachers’ voice and comparing the findings between two groups with many and few voice complaints.

Methods: Sixty female teachers of high school in Sari, north of Iran, were chosen by available sampling to participate in this cross-sectional study. According to a voice complaints questionnaire, 21 subjects located in few voice complaints and 31 in many voice complaints group. After a working day, subjects completed a voice self-assessment questionnaire. Also, teachers’voice were recorded during three tasks including sustained vowels /a/ and /i/, text reading and conversational speech. Acoustic parameters were analyzed by Praat software and 2 speech-language pathalogists performed auditory-perceptual assessment by GRBAS ( Grade, Roughness, Breathiness, Asthenia, Strain ) scale.

Results: Comparing of the voice self-assessment between the two groups demonstrated statistically significant difference (p<0.05) however results of the acoustic and auditory-perceptual measurement did not show significant diffrence.

Conclusion: Despite prevalent voice problems in teachers, there are various conditions in terms of complaints and assessments methods. In this study, only a remarkable deviation documented in the client-based assessments in many voice compliants group in comparison with few voice compliants, which would be probably related to different individual’s perception of voice problem between two groups. These results support paying attention to self-assessments in clinical process of voice problems.

Background and Aim: Auditory-perceptual assessment of voice a main approach in the diagnosis and therapy improvement of voice disorders. Despite, there are few Iranian studies about auditory-perceptual assessment of voice. The aim of present study was development and determination of validity and rater reliability of Persian version of the Consensus Auditory Perceptual Evaluation of Voice (CAPE -V).

Methods: The qualitative content validity was detected by collecting 10 questionnaires from 9 experienced speech and language pathologists and a linguist. For reliability purposes, the voice samples of 40 dysphonic (neurogenic, functional with and without laryngeal lesions) adults (20-45 years of age) and 10 normal healthy speakers were recorded. The samples included sustain of vowels and reading the 6 sentences of Persian version of the consensus auditory perceptual evaluation of voice called the ATSHA.

Results: The qualitative content validity was proved for developed Persian version of the consensus auditory perceptual evaluation of voice. Cronbach’s alpha was high (0.95). Intra-rater reliability coefficients ranged from 0.86 for overall severity to 0.42 for pitch inter-rater reliability ranged from 0.85 for overall severity to 0.32 for pitch (p<0.05).

Conclusion: The ATSHA can be used as a valid and reliable Persian scale for auditory perceptual assessment of voice in adults.