Voice quality in patients with temporomandibular disorders.

OBJECTIVES: This study assessed the voice quality in TMD patients compared to healthy individuals using the Dysphonia Severity Index (DSI) and evaluated the correlation between the DSI and TMD severity. METHODS: Patients who had TMD with Fonseca's anamnestic index were subjected to an examination based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). A sample of 35 patients with TMD and 36 healthy subjects were included in the study. RESULTS: There were significant differences in the DSI score and its components between healthy subjects and TMD patients (p < .001). A significant correlation was found between the DSI scores and TMD severity (Spearman's rho: -0.90, p < .001). CONCLUSION: Patients with TMD demonstrated lower DSI scores and lower voice quality compared to healthy subjects.

Investigation of the effectiveness of articulation therapy through tele-practice on children with cleft palate in Khuzestan Province during COVID-19 pandemic.

INTRODUCTION: A cleft palate is a common type of facial malformation. Compensatory articulation errors are one of the important causes of unclear speech in children with cleft palate. Tele-practice (TP) helps to connect therapists and clients for assessment and therapy. Our goal is to investigate the effectiveness of articulation therapy through tele-practice on cleft palate children in Khuzestan Province during the COVID-19 pandemic. MATERIALS & METHODS: Before starting the treatment, a 20-min speech sample was recorded individually from all the children. Speech intelligibility and the percentage of correct consonants were assessed for each speech sample. The control group received treatment sessions in person at the cleft palate center, and the other group received treatment via tele-practice using the ZOOM platform. Treatment sessions were provided in the form of 45-60-min group sessions, twice a week, for 5 weeks (10 sessions in total). After 10 treatment sessions, the speech sample was recorded again. The level of parental satisfaction was measured using a Likert 5-level survey. RESULTS: The mean score of intelligibility of the two groups decreased (-1.4400 and 0.7200). The two groups' mean percentage of correct consonants increased. (26.09 and 17.90). In both groups, the mean score of parents' satisfaction with the treatment was high (3.44 and 3.84). The mean of difference before and after the speech intelligibility and the percentage of correct consonants variables in both groups was statistically significant (P = 0.001 and P = 0.002, respectively). In both groups, the satisfaction variable was not associated with a statistically significant difference (P = 0.067). CONCLUSION: The effectiveness of in-person therapy over a certain period of time is higher than tele-practice. Nevertheless, the results demonstrated an increase in the intelligibility of speech and the percentage of correct consonants in both groups, thus proving the effectiveness of articulation therapy in correcting compensatory articulation errors in children with cleft palate through in-person and tele-practice.

The effects of transcutaneous electrical nerve stimulation on muscle activity pattern in professional voice users with muscle tension dysphonia using surface electromyography data: A pilot study.

OBJECTIVES: Muscle Tension Dysphonia is a voice disorder, which results in stiffness in the laryngeal extrinsic muscles, intense collision, painful contractions, and vibrations of the vocal cords. Due to the multifactorial identity of Muscle Tension Dysphonia, its therapeutic approach must be multidisciplinary. METHODS: The participants were divided into two groups: a control group (5participants) that received Circumlaryngeal Manual Therapy (CMT) + Placebo Transcutaneous Electrical Nerve Stimulation and an experimental group (5participants) that received Transcutaneous Electrical Nerve Stimulation + CMT. Both groups received 10 sessions of treatment, twice a week, for 40 min each. Before and after treatment, participants were assessed using the Dysphonia Severity Index (DSI) and surface electromyography for their ability to sustain the vowels /e& u/and count from 20 to30. RESULT: After therapy, there were substantial improvements in the DSI (2.72 ± 0.55, P < 0.05) and muscle electrical activity in the control group. The DSI (3.66 ± 0.63, P < 0.05) and muscle electrical activity were also significantly improved in the experimental group after treatment. The findings of the between-group comparison after treatment revealed a significantly greater increase in the Dysphonia Severity Index in the experimental group compared with the control group (P = 0.037). Although there was no significant difference between the two groups in terms of muscle electrical activity, clinically significant changes were more noticeable in the experimental group when compared with the control group. CONCLUSIONS: Positive results were seen in both groups. The results demonstrate that both approaches relax vocal tract muscles. As a result, Transcutaneous Electrical Nerve Stimulation was recommended as a complementary treatment for clients with Muscle Tension Dysphonia.

Multi-scale model of lumen formation via inverse membrane blebbing mechanism during sprouting angiogenesis process.

Cancer is one of the leading causes of mortality and morbidity among people worldwide. Cancer appears as solid tumors in many cases. Angiogenesis is the growth of blood vessels from the existing vasculature and is one of the imperative processes in tumor growth. Another vital phenomenon for formation and functionality of this vasculature network is lumen formation. The results of recent studies indicate the importance of blood pressure in this mechanism. Computational modeling can study these processes in different scales. Hence, wide varieties of these models have been proposed during recent years. In this research, a multi-scale model is developed for the angiogenesis process. In the extracellular scale, the growth factor concentration is calculated via the reaction diffusion equation. At the cellular scale, growth, migration, and the adhesion of endothelial cells are modeled by the Potts cellular model. At the intra-cellular scale by considering biochemical signals, a Boolean network model describes migration, division, or apoptosis of endothelial cells. A stochastic model developed for lumen formation via inverse membrane blebbing mechanism. A CFD simulation was also used to investigate the role of pulsated blood pressure in the inverse membrane blebbing mechanism. The lumen formation model shows stochastic behavior in blebs expansion and lumen expansion. Comparing the stochastic model's results with the CFD simulation also shows the vital role of pressure pulse and the topology of the blebs in bleb retraction.

Immediate Effects of Semi-occluded Vocal Tract Exercises as a Vocal Warm-Up in Singers.

OBJECTIVE: The present study aimed to investigate the Immediate Effects of Semi-occluded Vocal Tract Exercises (SOVTEs) as a vocal warm-up on the Electrical Activity of Extrinsic Laryngeal Muscles and acoustic parameters of voice in singers. STUDY DESIGN: This study used a pre-/post-interventional (quasi-experimental) design and a simple non-random sampling method. SETTING: Musculoskeletal Rehabilitation Research Center. METHOD: Surface electromyography of the suprahyoid and infrahyoid muscle areas and acoustic measurements were assessed before and immediately after performing three SOVTEs: lip-trill, humming, and straw phonation for 20 minutes as a vocal warm-up in eleven healthy male singers with an average age of 26.5 ± 4.2. RESULTS: After performing the vocal warm-up, root mean square in channels two and three (left and right infrahyoid muscle areas) in all vocal tasks, including /i/, /u/, and counting from 20 to 30 was significantly decreased (P < 0.05). The acoustic parameters, F1, and F1-F0 difference were significantly decreased (P < 0.05). CONCLUSION: The results suggest that after performing SOVTEs as a vocal warm-up, the electrical activity of the extrinsic laryngeal muscles is reduced. The acoustic analysis also demonstrated a decrease in F0, F1, and F1-F0 variables. Therefore, it seems that the results of acoustic and electromyographic assessments are in line and it is likely that SOVTEs through the vocal economy lead to a reduction in the load applied to the phonatory system.

Comparison of verbal fluency in monolingual and bilingual elderly in Iran.

Verbal fluency is one of the first and most important cognitive functions that deteriorate during the aging process. Verbal fluency is defined as the skill and speed of finding words and finding semantic and phonetic connections between words. One of the most important factors in verbal fluency is bilingualism. Therefore, the current study aimed to investigate the effect of bilingualism on the verbal fluency of the elderly in Iran. A total of 12 normal elderly bilingual (Arabic-Persian) speakers and 12 normal elderly monolingual (Persian) speakers participated in this comparative-analytical study. To assess verbal fluency, two semantic and phonetic fluency tasks were used. Data were analyzed using the Wilcoxon-Mann-Whitney tests. The results obtained from the comparison of phonetic fluency and semantic fluency of native languages of the two groups showed a better performance of monolingual participants in semantic fluency and phonetic fluency tasks in Persian language compared to the Arabic bilingual elderly. No difference was observed in verbal fluency of Persian monolinguals and bilinguals. However, in bilingual elderly participants, faster retrieval was observed in Persian language than in Arabic. This can be considered in assessment and treatment measures for Arabic-Persian bilinguals.

Dysphonia Characteristics and Vowel Impairment in Relation to Neurological Status in Patients with Multiple Sclerosis.

PURPOSE: In this study, we attempted to assess the phonation and articulation subsystem changes in patients with multiple sclerosis compared to healthy individuals using Dysphonia Severity Index and Formant Centralization Ratio with the aim of evaluating the correlation between these two indexes with neurological status. MATERIALS AND METHODS: A sample of 47 patients with multiple sclerosis and 20 healthy speakers were evaluated. Patients' disease duration and disability were monitored by a neurologist. Dysphonia Severity Index and Formant Centralization Ratio scores were computed for each individual. Acoustic analysis was performed by Praat software; the statistical analysis was run using SPSS 21. To compare multiple sclerosis patients with the control group, Mann-Whitney U test was used for non-normal data and independent-samples t test for normal data. Also a logistic regression was used to compare the data. Correlation between acoustic characteristics and neurological status was verified using Spearman correlation coefficient and linear regression was performed to evaluate the simultaneous effects of neurological data. RESULTS: Statistical analysis revealed that a significant difference existed between multiple sclerosis and healthy participants. Formant Centralization Ratio had a significant correlation with disease severity. CONCLUSION: Multiple sclerosis patients would be differentiated from healthy individuals by their phonation and articulatory features. Scores of these two indexes can be considered as appropriate criteria for onset of the speech problems in multiple sclerosis. Also, articulation subsystem changes might be useful signs for the progression of the disease.

The Relationship Between Vocal Fatigue Index and Voice Handicap Index in University Professors With and Without Voice Complaint.

INTRODUCTION: University professors, just like teachers, are considered as professional voice users, who are subject to voice disorders and complaints due to their field of work. The present study aims to investigate the relationship between vocal fatigue index and voice handicap index in university professors with and without voice complaint. METHODS: This is a cross-sectional descriptive-analytic study that was conducted on 84 university professors with an average age of 38.27 ± 9.95. University professors were divided into two groups with and without voice complaints based on the opinion of the professors about the existence or absence of voice complaint. Data obtained from this study was analyzed using SPSS 22 software at a significant level of less than 0.05. RESULTS: There was a significant correlation between vocal fatigue index and voice handicap index in university professors (P <0.05). In the university professors without voice complaints, only the third factor of the vocal fatigue index was not significant (P > 0.05). However, in this group, there was a significant correlation between the first and the second factor of vocal fatigue index and voice handicap index (P < 0.05). CONCLUSION: The results of this study indicate the effect of vocal fatigue on the quality of life of university professors. University professors, like teachers, are exposed to voice disorders and, thus, complaints which leave impacts on their career and should be addressed as a group of professional voice users to prevent voice disorder among them.

Factor Analysis of the Persian Version of the Voice Disability Coping Questionnaire.

INTRODUCTION: Voice disorders can affect the quality of life and coping mechanisms and also coping mechanisms can affect the way in which patients deal with their voice problems. People with voice disorders need to use coping strategies to deal with the problems caused by their voice disorder. The purpose of this study was to examine the psychometric properties and cultural adaptation of the Voice Disability Coping Questionnaire in the Iranian population. METHODS: The translation and cross-cultural adaptation procedures were performed according to the basic rules and instructions set by the International Quality of Life Assessment Project. Two hundred and forty-eight adults (218 patients with voice disorder and 30 healthy controls) were participated in the study. Face and content validity, clinical validity, and construct validity of the questionnaire were investigated by modern psychometric methods. RESULTS: Quantitative methods were used to measure content validity and all items were detected applicable. This means that the final version was clear and easy to answer. Clinical validity shows that the Persian version of VDCQ can distinguish between patients and healthy controls (P < 0.001). The construct validity of the VDCQ was tested in a cross-sectional study. The questionnaire was analyzed by exploratory and confirmatory factor analyses. Investigation of initial communality and after extraction of factors by Varimax rotation method showed that the share of items for all items in the questionnaire except item 12, is higher than 0.5. Therefore, item 12 should be removed from the questionnaire (Table 3). Based on the confirmatory factor analysis model, items 2 and 10, whose factor load were less than 0.4, were excluded from the questionnaire (Fig. 1). For reliability the Cronbach's alpha coefficient and ICC were obtained as 0.82 and 0.99, respectively. The results of studying the role of items in the reliability of the VDCQ showed that all items increase internal consistency. CONCLUSION: Based on modern statistical analysis conducted in this study, the original 15 item questionnaire was reduced to 12 item. The 12 item questionnaire is a valid and reliable tool for quantifying coping strategies in people with voice disorder.

Reliability, validity, and normative investigation of Persian version of a High-Level Language Test (BESS).

Our study aimed at reliability, validity, and normative investigation of the Persian version of the High-Level Language Test (BESS). This study was conducted on 60 multiple sclerosis (MS) patients as well as 60 healthy individuals. After translating the BESS into Persian, its content validity was determined based on 10 experts working in the same field. The reliability of the test was determined using techniques such as the test-retest method, Cronbach's alpha, and clinical validity. The content validity ratio (CVR) was higher than 0.62 for every subtest, and the content validity index (CVI) was between 0.1 and 0.8 for all subtests. Cronbach's alpha coefficient was between 0.70 and 0.93, and intraclass correlation coefficient (ICC) was between 0.80 and 0.96. Clinical validity results showed a significant difference between means of patients' scores and healthy subjects scores (p ≤ 0.005). The Persian version of BESS benefits from high reliability and validity values. Speech therapists can use the test to examine high-level language disorders in MS patients.

The Efficacy of Phonological Processing Treatment on Stuttering Severity in Persian Pre-School Children.

OBJECTIVES: Correct phonological encoding is crucial to fluent speech production. Phonological working memory and phonological awareness are important phonological processes that affect phonological encoding. The purpose of this study was to investigate the effect of phonological processing on stuttering severity of Persian pre-school children. MATERIALS & METHODS: Six children were targeted in this study in Ahvaz City, southern Iran in 2018, with Quasi-experimental design (Before and after clinical trial). These children participated in a treatment protocol, scheduled in 13-sessions. The treatment protocol of the phonological processing included nonword repetition in the phonological working memory and phonological awareness therapy. Overall, 30 nonwords were taken to examine the phonological working memory. The Persian test of language development was taken to examine phonological awareness. Stuttering severity measurements were performed with pre- and post-treatment. The severity rating was instructed to the parents based on Guitar protocol. They were asked to keep score every day until the end of the treatment sessions, and they reported the score to the therapist. RESULTS: The stuttering severity score in pre and post-treatment was significant (P=0.027), and in the follow-up, phase was not significant (P=0.236); stuttering severity was reduced in children who stutter. Moreover, the severity rating score reported by parents during treatment was significant (P= 0.0001). This showed a reduction in stuttering severity. CONCLUSION: The poor performance of phonological awareness and phonological working memory in phonological processing affect stuttering severity. Treatment of sub-systems of phonological processing can have an important role in reducing stuttering severity and increasing speech fluency.

Cross-Cultural Adaptation and Validation of the Vocal Fatigue Index into Persian.

INTRODUCTION: The aim of the present study was the cross-cultural adaptation and validation of the Vocal Fatigue Index (VFI) in Persian. METHODS: The English version of the VFI was translated to Persian using the guidelines of International Quality of Life Assessment. Eighty participants with voice disorders and 50 healthy controls without any voice disorders completed the Persian version of the VFI. The 80 participants with voice disorders completed the VFI a second time a week from the initial completion to evaluate test-retest reliability. RESULTS: The VFI measure demonstrated a strong internal consistency. Cronbach alpha coefficient was 0.95 for tiredness and avoidance of voice use, 0.86 for physical discomfort and 0.83 for improvement or lack thereof of symptoms with voice rest. VFI also showed a high test-retest reliability (r = 0.75-0.89). CONCLUSIONS: The Persian version of the VFI is considered to be a valid and reliable questionnaire for identifying individuals with probable vocal fatigue. The VFI can be utilized in clinics across Iran in the assessment and treatment of individuals with vocal fatigue.

Diagnostic evaluation of dysphagia in multiple sclerosis patients using a Persian version of DYMUS questionnaire.

BACKGROUND: Multiple sclerosis is a chronic neurological disease that may cause swallowing disorders. Dysphagia is a common problem, which patients with different levels of disability may encounter, but it is usually underestimated; therefore, effective assessments need to be performed before any serious complications. The aim of this study was to identify the frequency and characteristics of dysphagia in multiple sclerosis patients of Khuzestan MS society, using a Persian version of Dysphagia in Multiple Sclerosis (DYMUS) questionnaire. METHOD: 105 consecutive MS patients (84 F and 21 M, mean age 33.8 ± 8.5 years, mean disease duration 3.5 ± 3.1 years, mean Expanded Disability Status Scale (EDSS) 1.8 ± 1.3) participated in the study and the DYMUS questionnaire was administered by a trained speech therapist. RESULTS: The results have shown that 55 MS patients (52.4%) had dysphagia and the dysphagia was significantly associated with the disease course of MS (p = 0.02). However, significant associations between DYMUS values and EDSS, disease duration, age, and gender were not observed. (Respectively, p = 0.4, p = 0.09, p = 0.1, p = 1.0). In the dysphagia group, based on dysphagia severity, 17.1% and 35.2% of patients had mild and alarming dysphagia, respectively. Although, the patients with alarming dysphagia had longer disease duration, higher EDSS score and more with SP, PP and PR disease course than the patients with mild dysphagia, these differences were not significant. CONCLUSION: The oropharyngeal dysphagia in MS patients is very common even in early stages of the disease; therefore, it is important to assess these patients carefully and to initiate a treatment program if needed.

Gensini scores and well-being states among patients with coronary artery disease: A comparison study.

BACKGROUND: World Health Organization (WHO) considered Mental Health Continuum (MHC) as a good instrument for well-being studies. Moreover, gensini score (GS) is an intensity index for coronary artery disease (CAD). The aim of our study was to compare GSs among patients who had coronary artery disease with different well-being states. METHODS: This was a cross-sectional study conducted in Tehran Heart Center, Iran, in 2013. The study population consisted of 50 non-depressed patients who were candidates for coronary artery bypass graft (CABG). All of the participants were interviewed according to the Iranian version of Mental Health Continuum (IV-MHC) and were allocated to flourishing, maternal mental health (MMH) and languishing states based on the related classification criteria. GS was calculated for each participant. Data were analyzed by SPSS. RESULTS: Forty one (82%) patients were in flourishing, 9 (18%) in MMH and nobody was in languishing states. The mean (standard deviation) of GS was 90.43 (44.424) and 89.67 (33.378) for flourishing and MMH ones, respectively (P = 0.962). There was no statistically significant correlation between GSs and well-being states (all Ps > 0.050). CONCLUSION: Considering IV-MHC classification, all of our patients were only allocated to flourishing and MMH states. There was no relationship between intensity of CAD and the states (P > 0.050). We recommend further research with larger sample sizes for better evaluation of the Iranian version of the instrument.

A Comparative Study of Iranian Female Primary School Teachers' Quality of Life With and Without Voice Complaints.

OBJECTIVES/HYPOTHESIS: As the largest group of professional voice users, teachers are more likely to face voice disorders because of their specific job conditions. This study aimed to compare the quality of life in female teachers with and without voice complaints. STUDY DESIGN: This is a cross-sectional descriptive-analytical study. METHODS: This was a cross-sectional study of samples of primary school female teachers with (n = 60) and without (n = 60) voice disorders. All teachers were serving in Tehran, Iran. Professional background information was obtained through interviews, and quality of life was measured using the 36-item Short Form Health Survey questionnaire. A comparison was made between the study groups to analyze the data. RESULTS: The mean age of teachers was 44 (standard deviation = 3.95) years. There were no significant differences between the two groups regarding their professional background. However, significant differences were observed between the two groups in all subscales of the 36-item Short Form Health Survey, including physical and social functioning, role limitations because of either physical or emotional problems, bodily pain, general health, vitality, and mental health (P < 0.05). CONCLUSION: Findings of this study point to the effect of voice complaint on quality of life and showed that teachers with voice complaints suffer from poor health-related quality of life. Therefore, both voice-specific and unspecific assessment methods are required for clinical diagnostics.

Relationship Between Voice and Motor Disabilities of Parkinson's Disease.

To evaluate voice of Iranian patients with Parkinson's disease (PD) and find any relationship between motor disabilities and acoustic voice parameters as speech motor components. We evaluated 27 Farsi-speaking PD patients and 21 age- and sex-matched healthy persons as control. Motor performance was assessed by the Unified Parkinson's Disease Rating Scale part III and Hoehn and Yahr rating scale in the "on" state. Acoustic voice evaluation, including fundamental frequency (f0), standard deviation of f0, minimum of f0, maximum of f0, shimmer, jitter, and harmonic to noise ratio, was done using the Praat software via /a/ prolongation. No difference was seen between the voice of the patients and the voice of the controls. f0 and its variation had a significant correlation with the duration of the disease, but did not have any relationships with the Unified Parkinson's Disease Rating Scale part III. Only limited relationship was observed between voice and motor disabilities. Tremor is an important main feature of PD that affects motor and phonation systems. Females had an older age at onset, more prolonged disease, and more severe motor disabilities (not statistically significant), but phonation disorders were more frequent in males and showed more relationship with severity of motor disabilities. Voice is affected by PD earlier than many other motor components and is more sensitive to disease progression. Tremor is the most effective part of PD that impacts voice. PD has more effect on voice of male versus female patients.

High crash areas resulting in injuries and deaths in Tehran traffic areas from november 2011 through february 2012: a geographic information system analysis.

BACKGROUND: Evaluation of intra-city roads in terms of environmental factors of motor vehicle injuries can help us to better identify these factors and the share of each of the factors in injuries. Therefore, this study was conducted to determine the high injury areas and the risk factors of motor vehicle crashes resulting in injury and death in Tehran, the capital city of Iran, from November 2011 through February 2012. METHODS: In this cross sectional study, the locations of the motor vehicle injuries resulting in injuries and deaths were obtained from police stations in Tehran. The coordinates of the injuries locations were extracted and entered into the Arc-GIS software to overlay the different layers of geographical data and extract the risk map. RESULTS: A total of 4257 motor vehicle injuries were evaluated in this study. Forty-two injuries (1%) resulted in death and 4215 injuries (99%) resulted in injury. The traffic districts 5 and 21 had the highest frequency of injuries resulting in death. The type of the motor vehicle resulting in injury or death was motorcycle in 2330 injuries (54.73%). CONCLUSION: The frequency of traffic injuries is more in the west and northwest areas of Tehran, and it is caused more by motorcycles in terms of traffic and motor injuries resulting in injury and death. It is useful to conduct more studies to better identify these factors considering their importance in traffic injuries.

Voice-related disability of Iranian patients with temporomandibular disorders.

INTRODUCTION: The relationship between handicaps because of voice disorders and temporomandibular disorders (TMDs) severity was examined. METHOD: Fifty-two Persian women with temporomandibular disorder (TMD) were examined by two dentists in separate sessions and the assessment protocol of the Dentistry Clinic of Tehran University of Medical Sciences was filled by both dentists and finally they gave their opinion separately about the existence of TMD and categorized the severity of TMD as mild, moderate, and severe. To assess perceived disability resulting from voice disorders in TMD patients, the voice handicap index (VHI) questionnaire was used. RESULTS: The total score of VHI in 80.8% of patients with TMD was equal to or more than 14.5. A significant positive relationship was found between the severity of TMD and the total score of VHI (P = 0.000, r = 0.79). CONCLUSIONS: It seems that a comprehensive voice assessment should be included in the evaluation of TMD, and considering different effects of voice disorders on patients' lives, a complete voice evaluation including voice-related disability is necessary to understand the nature of pathophysiology of TMD.

Cross-cultural adaptation and validation of the voice-related quality of life into Persian.

The purpose of this study was to adapt and determine reliability, validity, and responsiveness of voice-related quality of life (V-RQOL) for Persian. A total of 300 patients with voice disorders participated in the study. Also, 116 people without any voice disorders volunteered to participate in the study as a control group. All participants filled in the Persian version of V-RQOL. The reliability, validity, and responsiveness were studied. Results demonstrated that the discrimination coefficient is significant for all items. The V-RQOL measure showed a strong internal consistency (Cronbach alpha coefficient = 0.88-0.91) and a good test-retest reliability (r = 0.93-0.95). Pre- and post-treatment results showed a significant responsiveness (functioning, 0.000; social-emotional, 0.001; and total, 0.000). Effect size range of 1.26-1.59 and the standardized response mean range of 1.07-1.41 were obtained for V-RQOL. It seems that the Persian version of V-RQOL is valid, reliable, and responsive to change, and this questionnaire can be used for completing voice evaluation for patients with dysphonia.

Intrarater and interrater reliability of sagittal head posture: a novel technique performed by a physiotherapist and a speech and language pathologist.

INTRODUCTION: Different professionals such as speech and language pathologists and voice scientists are involved in the evaluation of head and neck posture. Therefore, a reliable, time-efficient, and precise method of posture assessment is essential for use in clinical and research settings. Photogrammetry is one of the most commonly used methods to assess head and neck posture. The objectives of this study were to evaluate the intrarater reliability of the method with a large sample size and the interrater reliability by two different specialists (a physiotherapist and a speech and language pathologist). METHOD: A total of three hundred four subjects (144 males and 160 females) aged between 18 and 28 years participated in the study. During the test session, a photograph was taken of the left-side profile of each subject in their ordinary and comfortable position. The head posture angle of each picture was calculated by two raters. The whole procedure was repeated in a retest session, 24 hours later. A total number of eight analyses were performed for each subject. The reliability was evaluated at several stages hierarchically and after confirming the reliability in each step, the next step was investigated. Paired t tests on the differences of scores obtained at all the aforementioned stages were used to ensure the absence of any systematic bias. To assess the reliability, intraclass correlation coefficients (ICCs) and the standard error of measurements (SEMs) were calculated. RESULTS: There was no significant difference between the mean values of the test and the retest angles at any stage of calculating the head posture angle in both pictures by both examiners (P > 0.05). The ICC and SEM values calculated for all stages were between 0.86-0.97 and 0.52-1.53, respectively. CONCLUSION: Systematic bias has not occurred at any stage. The ICC and SEM values calculated have demonstrated that there were appropriate relative and absolute reliabilities in all stages. This method is suggested to be used simply in research and clinical areas by different specialists.