Public health policy-making for hearing loss: stakeholders' evaluation of a novel eHealth tool.

BACKGROUND: Hearing loss (HL) affects 466 million people of all ages worldwide, with a rapidly increasing prevalence, and therefore requires appropriate public health policies. Multi-disciplinary approaches that make use of eHealth services can build the evidence to influence public policy. The European Union-funded project EVOTION developed a platform that is fed with real-time data from hearing aids, a smartphone, and additional clinical data and makes public health policy recommendations based on hypothetical public health policy-making models, a big data engine and decision support system. The present study aimed to evaluate this platform as a new tool to support policy-making for HL. METHODS: A total of 23 key stakeholders in the United Kingdom, Croatia, Bulgaria and Poland evaluated the platform according to the Strengths, Weaknesses, Opportunities and Threats methodology. RESULTS: There was consensus that the platform, with its advanced technology as well as the amount and variety of data that it can collect, has huge potential to inform commissioning decisions, public health regulations and affect healthcare as a whole. To achieve this, several limitations and external risks need to be addressed and mitigated. Differences between countries highlighted that the EVOTION tool should be used and managed according to local constraints to maximise success. CONCLUSION: Overall, the EVOTION platform can equip HL policy-makers with a novel data-driven tool that can support public health policy-making for HL in the future.

[Assessment of temporary hearing changes related to work as a bartender]. / Ocena czasowych zmian sluchu zwiazanych z praca na stanowisku barmana.

BACKGROUND: Noise in entertainment industry often reaches high sound pressure levels. Nevertheless, the risk of hearing loss in this sector is insufficiently recognized. The aim of this study was the assessment of the relationship between noise exposure and temporary threshold shifts (TTS) for people working as bartenders at a variety of entertainment venues. MATERIAL AND METHODS: The study comprised a total of 18 bartenders (mean age was 25±7 years old) employed at a music club (N = 8), pub (N = 5) and discotheque (N = 5). Personal dosimeters were used for determining noise levels and frequency characteristics. Hearing was evaluated by pre- (before work) and post-exposure (up to 15 min after the end of work) pure tone audiometry. Hearing tests were carried out for bartenders during 2 or 3 sessions while working on weekends. RESULTS: The mean personal noise exposure level normalized to a nominal 8-hour working day was 95 dBA, above 4 times higher than the accepted legal limit. The TTS values (10 dB HL or more) were significant at 4 kHz for both ears for 77% of bartenders. CONCLUSIONS: People working as bartenders represent a professional group with an increased risk of hearing loss. Raising awareness of this fact and implementing hearing protection programs in this group of workers is urgently needed, in line with the European Commission Directive (EU Directive 2003/10/EC). Med Pr. 2019;70(1):17-25.

[Health criteria and scope of workers' periodic health check-ups for selected types of work and exposure factors - Nofer Institute of Occupational Medicine guidelines]. / Kryteria zdrowotne i zakres badan profilaktycznych dla wybranych rodzajów prac i czynników narazenia ­ wytyczne Instytutu Medycyny Pracy w Lodzi.

Workers' medical prophylactic examinations referred to in the Labor Code are one of the tasks of the occupational medicine services. They are regulated by law which has been in force for more than 20 years in unchanged form. During this period, new harmful, burdensome or dangerous to health factors appeared in the workplaces, for which no preventive health check-up standard was defined. In the meantime, the health criteria for drivers and persons applying for driving licenses have also been significantly liberalized. The above changes, the authors' own experience, comments and problems reported by physicians who provide workers' prophylactic health care and employers as well as analysis of literature related to workers' health care in other countries have created the need to harmonize and update guidelines on health requirements for selected types of work. In addition the scope and frequency of prophylactic examinations for exposures, which are not included in applicable legal acts, has been developed. Med Pr. 2019;70(1):125-37.

[Functional assessment of patients with vertigo and dizziness in occupational medicine]. / Badanie czynnosciowe osób z zawrotami glowy i zaburzeniami równowagi dla potrzeb medycyny pracy.

BACKGROUND: Balance assessment relies on symptoms, clinical examination and functional assessment and their verification in objective tests. Our study was aimed at calculating the assessment compatibility between questionnaires, functional scales and objective vestibular and balance examinations. MATERIAL AND METHODS: A group of 131 patients (including 101 women; mean age: 59±14 years) of the audiology outpatient clinic was examined. Benign paroxysmal positional vertigo, phobic vertigo and central dizziness were the most common diseases observed in the study group. Patients' symptoms were tested using the questionnaire on Cawthworne-Cooksey exercises (CC), Dizziness Handicap Inventory (DHI) and Duke Anxiety-Depression Scale. Berg Balance Scale (BBS), Dynamic Gait Index (DGI), the Tinetti test, Timed Up and Go test (TUG), and Dynamic Visual Acuity (DVA) were used for the functional balance assessment. Objective evaluation included: videonystagmography caloric test and static posturography. RESULTS: The study results revealed statistically significant but moderate compatibility between functional tests BBS, DGI, TUG, DVA and caloric results (Kendall's W = 0.29) and higher for posturography (W = 0.33). The agreement between questionnaires and objective tests were very low (W = 0.08-0.11).The positive predictive values of BBS were 42% for caloric and 62% for posturography tests, of DGI - 46% and 57%, respectively. CONCLUSIONS: The results of functional tests (BBS, DGI, TUG, DVA) revealed statistically significant correlations with objective balance tests but low predictive values did not allow to use these tests in vestibular damage screening. Only half of the patients with functional disturbances revealed abnormal caloric or posturography tests. The qualification to work based on objective tests ignore functional state of the worker, which may influence the ability to work. Med Pr 2018;69(2):179-189.

Screening value of V-RQOL in the evaluation of occupational voice disorders.

BACKGROUND: Given the growing number of occupational voice users, easy and quick broad-scale screening is necessary to provide prophylaxis of voice disorders. The aim of the study was to assess applicability of the Voice Related Quality of Life questionnaire (V-RQOL) to screening occupational voice disorders. MATERIAL AND METHODS: The research comprised 284 subjects divided into 3 groups: 0 - the control group of normophonic subjects, non-professional voice users (N = 60), 1 - occupational voice users with objectively confirmed voice disorders (N = 124), 2 - the non-randomized group of occupational voice users with and without voice problems (N = 100). Self-assessment of voice was performed by means of the V-RQOL in comparison to the Voice Handicap Index (VHI). The relation between the V-RQOL and VHI was determined by means of linear regression. Receiver Operating Characteristic (ROC) curves were constructed and the cut-off point of the VRQOL was determined to discriminate between normophonic and dysphonic subjects. RESULTS: The relationship between the VHI and V-RQOL scores indicated a satisfactory coefficient of determination: R2 = 0.7266. High values of Cronbach's α confirmed high reliability of the V-RQOL test (0.867). Voice-Related Quality of Life questionnaire (V-RQOL) results were significantly worse in the study group than for normophonic controls (p < 0.001). The cut-off point for the test was set at 79 points. The determined area under the curve (AUC) = 0.910 (p < 0.001) showed high diagnostic accuracy of the V-RQOL. Results of the VRQOL differed for diagnose-based subgroups of dysphonic patients. CONCLUSIONS: The study gives grounds for application of the V-RQOL as a reliable tool for screening occupational voice disorders. Med Pr 2018;69(2):119-128.

[Evaluation of on-the-job noise exposure in the case of bartenders]. / Ocena narazenia na halas na stanowiskach pracy barmanów.

BACKGROUND: In places associated with the entertainment industry in which music is performed or played, sounds with high sound pressure levels may occur. Such exposure is a threat to both people spending their free time at concerts, in discos or pubs, as well as employees in these places. The aim of the research conducted in 2017 was to assess on-the-job noise exposure in the case of bartenders at various premises of the entertainment industry. MATERIAL AND METHODS: The measurements included 15 entertainment venues in Lódz, out of which 3 were selected: a music club, disco and pub. The exposure measurements were taken together for 4 work stations for bartenders using individual dosimetry in accordance with the PN-EN ISO 9612: 2011 standard. RESULTS: A total of 64 measurements were carried out, which showed that the equivalent sound levels A at the bartenders' workplaces vary considerably depending on the type of premises and the day of the week and the range of 67.6-108.7 dB. The highest sound levels occurred during the weekend (Fridays and Saturdays). The determined daily noise exposure levels exceeded the threshold of preventive action (80 dB) in 95% of the analyzed cases. Exceeding the maximum permissible noise level (NDN = 85 dB) was found in 66% of cases. CONCLUSIONS: It has been found that on-the-job noise levels in the case of bartenders significantly exceed the acceptable values of exposure levels and pose a risk of hearing damage. Med Pr 2018;69(6):633-641.

Laryngeal manual therapy palpatory evaluation scale: A preliminary study to examine its usefulness in diagnosis of occupational dysphonia.

BACKGROUND: The aim of this study has been to assess the larynx and soft tissue around the vocal tract in a group of people with healthy voice, and in a group of patients with occupational dysphonia using the new laryngeal manual therapy palpatory evaluation scale (LMTPE). MATERIAL AND METHODS: The examinations were performed in a study (dysphonic) group of professional voice users who had developed voice disorders (N = 51) and in the control group of normophonic subjects (N = 50). All the participants underwent perceptual voice assessment and examination by means of the LMTPE scale. Additionally, phoniatric examination including VHI (Voice Handicap Index) questionnaire, GRBAS (the Grade of hoarseness, Roughness, Breathiness, Asthenic, Strained) perceptual evaluation, maximum phonation time (MPT) measurement and videostroboscopy was performed in the study group. RESULTS: The comparison of the LMTPE total score showed that the results of the study group were significantly poorer than those of controls (p < 0.001). In the study group, correlations were found between the LMTPE results and the VHI scores (p < 0.05), perceptual evaluation by the GRBAS (p < 0.05) and the objective parameter MPT (p < 0.05). CONCLUSIONS: The study has proven that the LMTPE scale is characterized by the high score of Cronbach's α ratio estimating the reliability of the test. The results have confirmed that the LMTPE scale seems to be a valuable tool, useful in diagnostics of occupational dysphonia, particularly of hyperfunction origin. Med Pr 2017;68(2):179-188.

ICBEN review of research on the biological effects of noise 2011-2014.

The mandate of the International Commission on Biological Effects of Noise (ICBEN) is to promote a high level of scientific research concerning all aspects of noise-induced effects on human beings and animals. In this review, ICBEN team chairs and co-chairs summarize relevant findings, publications, developments, and policies related to the biological effects of noise, with a focus on the period 2011-2014 and for the following topics: Noise-induced hearing loss; nonauditory effects of noise; effects of noise on performance and behavior; effects of noise on sleep; community response to noise; and interactions with other agents and contextual factors. Occupational settings and transport have been identified as the most prominent sources of noise that affect health. These reviews demonstrate that noise is a prevalent and often underestimated threat for both auditory and nonauditory health and that strategies for the prevention of noise and its associated negative health consequences are needed to promote public health.

AUDITORY TEMPORAL PROCESSING TESTS - NORMATIVE DATA FOR POLISH-SPEAKING ADULTS.

BACKGROUND: Several subjects exposed to neurotoxins in the workplace need to be assessed for central auditory deficit. Although central auditory processing tests are widely used in other countries, they have not been standardized for the Polish population. The aim of the study has been to evaluate the range of reference values for 3 temporal processing tests: the duration pattern test (DPT), the frequency pattern test (FPT) and the gaps in noise test (GIN). MATERIAL AND METHODS: The study included 76 normal hearing individuals (38 women, 38 men) at the age of 18 to 54 years old (mean ± standard deviation: 39.4±9.1). All study participants had no history of any chronic disease and underwent a standard ENT examination. RESULTS: The reference range for the DPT was established at 55.3% or more of correct answers, while for the FPT it stood at 56.7% or more of correct answers. The mean threshold for both cars in the GIN test was defined as 6 ms. In this study there were no significant associations between the DPT, FPT and GIN results and age or gender. Symmetry between the ears in the case of the DPT, FPT and GIN was found. CONCLUSIONS: Reference ranges obtained in this study for the DPT and FPT in the Polish population are lower than reference ranges previously published for other nations while the GIN test results correspond to those published in the related literature. Further investigations are needed to explain the discrepancies between normative values in Poland and other countries and adapt tests for occupational medicine purposes.

[THE APPLICATION OF SHORT-TERM EFFICIENCY ANALYSIS IN DIAGNOSING OCCUPATIONAL VOICE DISORDERS]. / ZASTOSOWANIE KRÓTKOOKRESOWEJ ANALIZY WYDOLNOSCIOWEJ W DIAGNOZOWANIU ZABURZEN GLOSU O PODLOZU ZAWODOWYM.

BACKGROUND: An objective determination of the range of vocal efficiency is rather difficult. The aim of the study was to assess the possibility of application of short-term acoustic efficiency analysis in diagnosing occupational voice disorders. MATERIAL AND METHODS: The study covered 98 people (87 women and 11 men) diagnosed with occupational dysphonia throuigh videostroboscopic examination. The control group comprised 100 people (81 women and 19 men) with normal voices. The short-term acoustic analysis was carried out by means of DiagnoScope software, including classical parameters (Jitter group, Shimmer group and the assessment of noise degree NHR), as well as new short-term efficiency parameters determined in a short time period during sustained phonation of the vowel "a." The results were then compared. Results: The values of all the examined classical parameters were considerably higher in the study group of pathological voices than in the control group of normal voices (p = 0.00). The aerodynamic parameter, maximum phonation time, was significantly shorter by over 0.5 s in the study group than in the control group. The majority of the acoustic efficiency parameters were also considerably worse in the study group of subjects with occupational dysphonia than in the control group (p = 0.00). Moreover, the correlation between the efficiency parameters and most of the classical acoustic parameters in the study group implies that for the voices with occupational pathology the decreased efficiency of the vocal apparatus is reflected in the acoustic voice structure. CONCLUSIONS: Effliciency parameters determined during short-term acoustic analysis can be an objective indicator of the decreased phonatory function of the larnx, useful in diagnosing occupational vocal pathology.

The influence of jet engine noise on hearing of technical staff.

BACKGROUND: Due to high sound pressure levels (SPLs), noise produced by jet planes may be harmful to hearing of people working in their proximity. The aim of this study was to assess the effects of exposure to jet engine noise on technical staff hearing. MATERIAL AND METHODS: The study comprised 60 men, aged 24-50 years, employed in army as technical staff and exposed to jet engine noise for 6-20 years. The control group were 50 non-noise exposed males, aged 25-51 years. Exposure to noise emitted by jet engines was evaluated. Pure-tone audiometry (PTA) and distortion product otoacoustic emissions (DPOAE) were recorded in both groups. RESULTS: Jet engines emitted broadband noise with spectrum dominated by components in the frequency range 315-6300 Hz (1/3-octave bands). Maximum A-weighted SPL during tests reached values of approx. 120-130 dB. Consequently, engine-servicing personnel (even in the case of a single engine test) was exposed to noise (at A-weighted daily noise exposure level above 95 dB) exceeding permissible levels. Averaged audiometric hearing threshold levels of technical staff were higher (≤ 17 dB HL, p < 0.001) than in the control group. Similarly, the DPOAE amplitude was lower (≤ 17 dB SPL, p < 0.01) in the noise-exposed subjects compared to the non-exposed ones. Significant reduction of DPOAE levels was mainly noted for high frequencies (3-6 kHz). CONCLUSIONS: Despite the usage of hearing protection devices, both PTA and DPOAE consistently showed poorer hearing in engine-servicing personnel vs. control group.

Contribution of genetic factors to noise-induced hearing loss: a human studies review.

Noise-induced hearing loss (NIHL) is a complex disease that results from the interaction of genetic and environmental factors. Over the last 10 years there has been a great increase in association studies trying to identify the susceptibility genes for NIHL in humans. They were conducted based on the candidate gene approach and comprised predominantly the group of oxidative stress genes, inner ear potassium recycling pathway genes and monogenic deafness genes, as well as other genes. So far, the most promising results were obtained for two genes encoding potassium ion channels (KCNQ4 and KCNE1), catalase (CAT), protocadherin 15 (PCDH15), myosin 14 (MYH14) and heat shock protein (HSP70), because they were replicated in two (Polish and Swedish) or three (Polish, Swedish and Chinese) populations, and were sufficient in size to yield high power for the detection of a causative allele. Today, the development of high-throughput genotyping methods allows the detection of hundreds and thousands of single nucleotide polymorphisms (SNPs) in a single array which undoubtedly will lead toward identification of new NIHL susceptibility genes. This in turn will contribute to the development of genetics tests that would allow for better protection of noise-exposed individuals and personalized treatment, if necessary.

Noise induced hearing loss: research in Central, Eastern and South-Eastern Europe and Newly Independent States.

The aim of this review was to summarize the studies on noise-induced hearing loss (NIHL) which were carried out in the countries of Central and Eastern Europe, South-East Europe, and former Soviet Union countries or Newly Independent States in the period from 1970 to 2012. The papers were identified by literature search of all accessible medical and other databases (Scopus, PubMed, Medline, etc.) using the terms "noise; hearing loss, NIHL" as key words and country denomination (in alphabetical order: Armenia, Azerbaijan, Belarus, Bulgaria, Bosnia and Herzegovina, Croatia, Czech Republic, Georgia, Hungary, Montenegro, Poland, Romania, Russian Federation, Serbia, Slovakia, Slovenia, former Yugoslavia, Ukraine). This review comprises both papers published in peer-reviewed international journals and articles from local sources. The main papers' topics included the assessment of the noise hazards in occupational, and very seldom in communal environment, and the prevalence of hearing impairment in employees. Simultaneously, attempts were undertaken to establish the relationship between the degree of hearing impairment and noise exposure. The effect of combined exposures to noise and vibration and/or otoxic chemicals was assessed as well. The influence of environmental, individual, and genetic risk factors on NIHL development was intensively examined. In addition, studies concerning the role of otoacoustic emissions for NIHL monitoring and clinical examinations were conducted. Some animal researches, including molecular genetics, had been also performed. The majority of papers concerned occupational exposures, whereas only a few were dedicated to community noise.

[The influence of organic solvents on hearing and balance: a literature review]. / Dzialanie wybranych rozpuszczalników organicznych na narzad sluchu i uklad równowagi.

This manuscript presents an overview of current knowledge on the influence of organic solvents on the hearing and balance systems. The authors analyzed--the literature data concerning the results of all human and the most relevant animal studies, published untill 2012. Moreover, the guidelines for occupational medicine specialists were proposed on the basis of literature review and the authors' own scientific experience. The literature data and our studies revealed the increased risk of hearing loss in workers exposed to organic solvents only, and well documented potentiation of harmful effects of combinedexposure to organic solvents and noise. Hearing impairment is mainly observed in high frequencies, but lower frequencies can also be involved (0.5-4 kHz). The impairment induced by exposure to organic solvents is mild, up to several dBs. In the combined exposure to noise and solvents, the noise effect predominates. Organic solvents affect the central pathways of vestibular system although unilateral or bilateral vestibular hypofunction might also be a possible consequence of solvent exposure. Occupational exposure to organic solvents is a risk factor for hearing and balance impairments. Therefore, workers exposed to solvents should be covered by hearing loss prevention programs. Speech in noise test (HINT) and posturography seem to be the most suitable tests for hearing and balance prevention programme for organic solvent exposed workers.

[Nonlinear acoustic analysis in the evaluation of occupational voice disorders]. / Nieliniowa analiza akustyczna w ocenie zawodowych zaburzen glosu.

BACKGROUND: Over recent years numerous papers have stressed that production of voice is subjected to the nonlinear processes, which cause aperiodic vibrations of vocal folds. These vibrations cannot always be characterized by means of conventional acoustic parameters, such as measurements of frequency and amplitude perturbations. Thus, special attention has recently been paid to nonlinear acoustic methods. The aim of this study was to assess the applicability of nonlinear cepstral analysis, including the evaluation of mel cepstral coefficients (MFCC), in diagnosing occupational voice disorders. MATERIAL AND METHODS: The study involved 275 voice samples of pathologic voice (sustained vowel "a" and four standardized sentences) registered in female teachers with the occupation-related benign vocal fold masses (BVFM), such as vocal nodules, polyps, and 200 voice samples of normal voices from the control group of females. The mean age of patients and controls was similar (45 vs. 43 years). Voice samples from both groups were analyzed, including MFCC evaluation. RESULTS: MFCC classification using the Sammon Mapping and Support Vector Machines yielded a considerable accuracy of the test. Voice pathologies were detected in 475 registered voice samples: for vowel "a" with 86% sensitivity and 90% specificity, and for the examined sentences the corresponding values varied between 87% and 100%, respectively. CONCLUSIONS: Nonlinear voice analysis with application of mel cepstral coefficients could be a useful and objective tool for confirming occupational-related lesions of the glottis. Further studies addressing this problem are being carried out.

[Comparison of vocal tract discomfort scale results with objective and instrumental phoniatric parameters among teacher rehabilitees from voice disorders]. / Porównanie wyników skali dyskomfortu traktu glosowego z obiektywnymi i instrumentalnymi parametrami badania foniatrycznego u nauczycieli rehabilitowanych z powodu zaburzen glosu.

BACKGROUND: Diagnostic and therapeutic procedures of occupational dysphonia play a major role in voice self-assessment, which is one of the elements of a comprehensive evaluation of voice disorders. The aim of the study was to assess the applicability of the Vocal Tract Discomfort (VTD) scale to monitor the effectiveness of voice rehabilitation and compare the VTD results with objective and instrumental methods of phoniatric diagnosis. MATERIALS AND METHODS: The study included 55 teachers (mean age, 47.2) with occupational dysphonia. A comprehensive diagnosis took into account self-assessment by VTD scale, phoniatric examination, including laryngovideostroboscopy (LVSS) and objective measurements of the aerodynamic parameter - the maximum phonation time (MPT). After 4 months of intense rehabilitation, post-therapy examination was performed using the methods specified above. RESULTS: After the treatment, a significant improvement was obtained in the subjective symptoms measured on a VTD scale - assessed both for the frequency (p = 0.000) and the severity (p = 0.000) subscales. Positive effects of the therapy were also observed for the parameters evaluated in the phoniatric study (p < 0.01) and laryngovideostroboscopy (p < 0.01). After voice therapy, there was also an improvement in the objective parameter MCF, which was about 5 seconds longer. Studies have shown that the VTD scale is characterized by high reliability - Cronbach's alpha coefficient in the preliminary test was as follows: for the frequency subscale symptoms - 0.826, and severity - 0.845; similarly high reliability was achieved in the control test, 0.908 and 0.923, respectively. CONCLUSIONS: Vocal Tract Discomfort scale can be a valuable tool for assessing voice, and can also be used to monitor the effectiveness of therapy of the occupational dysphonia.

[Comparison of cepstral coefficients to other voice evaluation parameters in patients with occupational dysphonia]. / Porównanie wyników analizy cepstralnej z innymi parametrami oceny glosu u pacjentów z dysfoniami zawodowymi.

UNLABELLED: BACKGROUND Special consideration has recently been given to cepstral analysis with mel-frequency cepstral coefficients (MFCCs). The aim of this study was to assess the applicability of MFCCs in acoustic analysis for diagnosing occupational dysphonia in comparison to subjective and objective parameters of voice evaluation. MATERIALS AND METHODS: The study comprised 2 groups, one of 55 female teachers (mean age: 45 years) with occupational dysphonia confirmed by videostroboscopy and 40 female controls with normal voice (mean age: 43 years). The acoustic samples involving sustained vowels "a" and four standardized sentences were analyzed by computed analysis of MFCCs. The results were compared to acoustic parameters of jitter and shimmer groups, noise to harmonic ratio, Yanagihara index evaluating the grade of hoarseness, the aerodynamic parameter: maximum phonation time and also subjective parameters: GRBAS perceptual scale and Voice Handicap Index (VHI). RESULTS: The compared results revealed differences between the study and control groups, significant for MFCC2, MFCC3, MFCC5, MFCC6, MFCC8, MFCC10, particularly for MFCC6 (p < 0.001) and MFCC8 (p < 0.009), which may suggest their clinical applicability. In the study group, MFCC4, MFCC8 and MFCC10 correlated significantly with the major objective parameters of voice assessment. Moreover, MFCC8 coefficient, which in the female teachers correlated with all eight objective parameters, also showed the significant relation with perceptual voice feature A (asthenity) of subjective scale GRBAS, characteristic of weak tired voice. CONCLUSIONS: The cepstral analysis with mel frequency cepstral coefficients is a promising tool for evaluating occupational voice disorders, capable of reflecting the perceptual voice features better than other methods of acoustic analysis.

The adaptation of noise-induced temporary hearing threshold shift predictive models for modelling the public health policy.

OBJECTIVES: It has been shown that monitoring temporary threshold shift (TTS) after exposure to noise may have a predictive value for susceptibility of developing permanent noise-induced hearing loss. The aim of this study is to present the assumptions of the TTS predictive model after its verification in normal hearing subjects along with demonstrating the usage of this model for the purposes of public health policy. MATERIAL AND METHODS: The existing computational predictive TTS models were adapted and validated in a group of 18 bartenders exposed to noise at the workplace. The performance of adapted TTS predictive model was assessed by receiver operating characteristic (ROC) analysis. The demonstration example of the usage of this model for estimating the risk of TTS in general unscreened population after exposure to loud music in discotheque bars or music clubs is provided. RESULTS: The adapted TTS predictive model shows a satisfactory agreement in distributions of actual and predicted TTS values and good correlations between these values in examined bartenders measured at 4 kHz, and as a mean at speech frequencies (0.5-4 kHz). An optimal cut-off level for recognizing the TTS events, ca. 75% of young people (aged ca. 35 years) may experience TTS >5 dB, while <10% may exhibit TTS of 15-18 dB. CONCLUSIONS: The final TTS predictive model proposed in this study needs to be validated in larger groups of subjects exposed to noise. Actual prediction of TTS episodes in general populations may become a helpful tool in creating the hearing protection public health policy. Int J Occup Med Environ Health. 2023;36(1):125-38.

Noise-induced hearing loss.

Noise-induced hearing loss (NIHL) still remains a problem in developed countries, despite reduced occupational noise exposure, strict standards for hearing protection and extensive public health awareness campaigns. Therefore NIHL continues to be the focus of noise research activities. This paper summarizes progress achieved recently in our knowledge of NIHL. It includes papers published between the years 2008-2011 (in English), which were identified by a literature search of accessible medical and other relevant databases. A substantial part of this research has been concerned with the risk of NIHL in the entertainment sector, particularly in professional, orchestral musicians. There are also constant concerns regarding noise exposure and hearing risk in "hard to control" occupations, such as farming and construction work. Although occupational noise has decreased since the early 1980s, the number of young people subject to social noise exposure has tripled. If the exposure limits from the Noise at Work Regulations are applied, discotheque music, rock concerts, as well as music from personal music players are associated with the risk of hearing loss in teenagers and young adults. Several recent research studies have increased the understanding of the pathomechanisms of acoustic trauma, the genetics of NIHL, as well as possible dietary and pharmacologic otoprotection in acoustic trauma. The results of these studies are very promising and offer grounds to expect that targeted therapies might help prevent the loss of sensory hair cells and protect the hearing of noise-exposed individuals. These studies emphasize the need to launch an improved noise exposure policy for hearing protection along with developing more efficient norms of NIHL risk assessment.

Applicability of the vocal tract discomfort (VTD) scale in evaluating the effects of voice therapy of occupational voice disorders.

BACKGROUND: Occupational voice disorders are characterized by rich symptomatology, which is dominated by symptoms by the vocal tract discomfort. Therefore, in the management it is important to consider these subjective complaints. The aim of the study was to assess the usefulness of using the vocal tract discomfort scale (VTD) in evaluating the effects of rehabilitation concerning occupational dysphonia. MATERIAL AND METHODS: The study included 55 teachers (mean age: 47.2) with occupational dysphonia diagnosed by means of videostroboscopy. The test battery covered also: voice self-assessment according to voice handicap index (VHI), perceptual GRBAS scale and the new VTD scale. Each subject underwent intensive rehabilitation, including voice training and voice hygiene education. The post-therapy examination was conducted using the above-mentioned methods. RESULTS: Comparing the results obtained in the preliminary and the control test a significant post-therapy improvement (p = 0.000) was discovered in relation to the general outcome of the symptoms in the VTD scale-- assessed both as for the frequency subscale (24.7 points vs. 10 points) and the severity subscale (25.5 points vs. 10 points). A positive significant effect of the treatment was also observed in the voice VHI disability index (p < 0.05) and in perceptual voice evaluation, using the GRBAS scale (p < 0.05). In addition, the study revealed a high coefficient of correlation (r) between the subscales of the VTD, both in the preliminary examination (r = 0.934) and the control one (r = 0.935). CONCLUSIONS: The vocal tract discomfort scale (VTD) seems to be a valuable tool, useful in monitoring the progress in the treatment of occupational voice disorders.