Occupational elbow musculoskeletal disorders in Tunisia: Epidemiology and socio-professional consequences.

INTRODUCTION: Musculoskeletal disorders (MSDs) are as the primary occupational disease (OD) in Tunisia. They can touch the elbow and cause occupational disability. AIMS: Describe the epidemiological and clinical characteristics of elbow MSDs recognized in Tunisia, identify the factors associated with these MSDs and assess their socio-professional impact. METHODS: Retrospective descriptive study of elbow MSDs recognized as compensable OD by the Committees for the Recognition of Occupational Diseases of National Health Insurance Fund, in Tunisia, from 2012 to 2018. RESULTS: We collected 431 cases of elbow MSDs or 8.35% of all recognized MSDs and 11.8% of recognized MSDs during the same period. The average annual incidence was 4.3 cases. Patients had a mean age of 43.59 years and a clear female predominance (82.2%). The largest provider was the textile industry (60.6%). The average length of employment was 16.78 years. Biomechanical factors were repetitive movements (92.8%), forced movements (67.1%) and prolonged static posture (7.4%). These were lateral epicondylitis (79.1%), medial epicondylitis (14.2%) and ulnar nerve syndrome (10.7%). These pathologies were associated with other MSDs including carpal tunnel syndrome (25.8%). These MSDs were responsible for 15,342 days of lost work. The rate of permanent partial incapacity was 10.6% with a job loss in 15.63%. CONCLUSION: Elbow MSDs are responsible for heavy economic and socio-professional consequences justifying the implementation of a preventive strategy adapted within risk sectors.

A systematic review of work related musculoskeletal disorders among physical therapists and physiotherapists.

Physical therapists and physiotherapists (PPTs) perform and repeat physical tasks that can lead to work-related musculoskeletal disorders (WMSD). The aim was to study the main research concerning this problem, i.e. the risk factors, activities that exacerbate WMSD symptoms, alterations in work habits and the proposed responses, and to estimate mean value (±standard deviation, STD) for the most studied parameters. This review was conducted according to the PRISMA guideline. Five databases (Pubmed, ScienceDirect, Google Scholar, Medeley and Science.gov) were scanned to identify works investigating the different aspects of WMSD among PPTs. Two reviewers independently selected relevant studies using inclusion/exclusion criteria, critically appraised, and extracted data. To homogenize the data, prevalence were reported to the total sample studied when necessary. Among the 9846 articles identified, 19 articles were included. The WMSD prevalence was over 50 %. The areas most affected were the lower back, neck and thumb. An exhaustive list of parameters were constructed for job risk factors (n = 19), activities that exacerbating symptoms (n = 13), altered work habits (n = 15), responses and treatments (n = 26). The mean prevalence (±STD) was calculated for the major parameters. Nine main job risk factors were extracted with an average prevalence of about 30 % and a relatively high variability. Seven activities exacerbating WMSD symptoms and five altered work habits were identified with a homogeneous rate (5-20 %). Three main responses and treatments were found with heterogeneous prevalence. This review provides useful results for the development of future protocols to prevent the occurrence of WMSD among PPTs and meta-analyses.

Musculoskeletal disorders and quality of life for Chilean teachers during the COVID-19 pandemic at the academic year-end.

Introduction: Schoolteachers have reported multiple demands contributing to poor perceptions regarding their quality of life and high rates of musculoskeletal disorders. However, there are few studies about the association between musculoskeletal disorders and quality of life from the end of the academic period during the COVID-19 pandemic. Objective: Evaluate musculoskeletal disorders rates and their association with quality of life perceptions among teachers from the last academic period during the COVID-19 pandemic. Participants and methods: A total sample of 161 Chilean schoolteachers was included in a cross-sectional study musculoskeletal disorders prevalence was evaluated using the Standardized Nordic Questionnaire, and quality of life was evaluated through the Short-Form 12 Health Survey Instrument. A logistic regression was applied to evaluate the association between musculoskeletal disorders and quality of life perceptions adjusted by gender, age, and contract type. Results: 98% of teachers have suffered from some type of musculoskeletal disorders during the last 12 months, and 64% have had six or more painful regions. Women showed a higher musculoskeletal disorders rate than men. The group of teachers with the most musculoskeletal disorders (≥p50) saw significantly greater risk of low scores on the physical (OR: 2.16; p < 0.05) and mental components (OR: 4.86; p < 0.01) of quality of life, regardless of gender, age, and contract type. Conclusion: High musculoskeletal disorders rates suggest that preventive and informative actions must be taken regarding these disorders in order to protect teachers' mental and physical health, considering the effects of the school year and the COVID-19 health crisis.

Prevalence and associated factors of noise-induced hearing loss among workers in Bishoftu Central Air Base of Ethiopia.

Excessive occupational exposure to noise results in a well-recognized occupational hearing loss which is prevalent in many workplaces and now it is taken as a global problem. Therefore, this study aims to assess the prevalence of noise-induced hearing loss and associated factors among workers in the Bishoftu Central Air Base in Ethiopia. An institutional-based cross-sectional study was conducted among 260 central air base workers through face-to-face interviews, an environment noise survey, and an audiometric test for data collection. Data were entered by Epi-data version 3.1 and SPSS was used to analyze the data. Finally, a statistical analysis such as descriptive and binary logistic regression analysis was applied. A P-value < 0.05 at 95% CI was considered statistically significant. The overall prevalence of noise-induced hearing loss and hearing impairments was 24.6 and 30.9%, respectively. The highest prevalence of noise-induced hearing loss was recorded for workers who were exposed to noise levels greater than 90 dBA. Out of 132 workers exposed to the average noise level of 75 dB A, only 5% of workers were affected with noise-induced hearing loss, while 128 workers exposed to an average noise level equal to or greater than 90 dB A, 19.6% of workers were identified with noise-induced hearing loss. Regarding sex, around 21.9% of male workers were identified with noise-induced hearing loss. Workers who were exposed to a high noise level workplace previously or before the Central Air Base workplace were five times (AOR = 5.0, 95% CI 1.74-14.36) more likely affected by noise-induced hearing loss than those workers not previously exposed. Those workers who were exposed to greater or equal to 90dBA noise level were 4.98 times (AOR = 4.98, 95% CI 2.59-9.58) more likely to be exposed to noise-induced levels than those who were exposed to less than 90dBA noise level. Moreover, male air base workers were 3.5 times more likely exposed to hearing impairment than female workers (AOR = 3.5, 95% CI 1.01-12.0). This study identified that the prevalence of noise-induced hearing loss and hearing impairments was significantly high. So implementation of a hearing conservation program, giving noise education, and supplying adequate hearing protective devices (HPDs) are essentials.

Occupational tasks associated with shoulder pain and upper extremity disability: a cross-sectional study in the Johnston County Osteoarthritis Project.

BACKGROUND: Shoulder pain is a leading cause of disability. Occupations requiring high upper extremity demands may put workers at greater risk of shoulder injury and resulting pain. We examined associations of occupation with shoulder pain and upper extremity disability in the Johnston County Osteoarthritis Project. METHODS: Work industry and occupational tasks for the longest job held were collected from participants. At follow-up ranging from 4-10 years later, participants were asked about shoulder symptoms (pain, aching, or stiffness occurring most days of 1 month in the last year) and given a 9-item, modified Disabilities Arm Shoulder and Hand (DASH) questionnaire to categorize disability from 0-4 (none-worst). Logistic regression and cumulative logit regression models were used to estimate associations with prevalent shoulder symptoms and with worse disability category, respectively. Models were adjusted for cohort, age, sex, race, education and time to follow-up. Sex- and race-stratified associations were evaluated. RESULTS: Among 1560 included participants, mean age was 62 years (standard deviation ± 9 years); 32% were men, and 31% were Black. Compared to the managerial/professional industry, higher odds of both shoulder symptoms and worse upper extremity disability were seen for most industrial groups with physically demanding jobs, particularly the service industry. Work that often or always required lifting/moving > 10 lbs. was associated with higher odds of shoulder symptoms. Work that sometimes or always required heavy work while standing was associated with higher odds of shoulder symptoms, and this association was stronger among men and White workers. CONCLUSION: Physically demanding occupations were associated with increased occurrence of shoulder pain and disability. Mitigating specific physical work demands may reduce shoulder-related disability.

A blueprint for a new commercial driving epidemiology: An emerging paradigm grounded in integrative exposome and network epistemologies.

Excess health and safety risks of commercial drivers are largely determined by, embedded in, or operate as complex, dynamic, and randomly determined systems with interacting parts. Yet, prevailing epidemiology is entrenched in narrow, deterministic, and static exposure-response frameworks along with ensuing inadequate data and limiting methods, thereby perpetuating an incomplete understanding of commercial drivers' health and safety risks. This paper is grounded in our ongoing research that conceptualizes health and safety challenges of working people as multilayered "wholes" of interacting work and nonwork factors, exemplified by complex-systems epistemologies. Building upon and expanding these assumptions, herein we: (a) discuss how insights from integrative exposome and network-science-based frameworks can enhance our understanding of commercial drivers' chronic disease and injury burden; (b) introduce the "working life exposome of commercial driving" (WLE-CD)-an array of multifactorial and interdependent work and nonwork exposures and associated biological responses that concurrently or sequentially impact commercial drivers' health and safety during and beyond their work tenure; (c) conceptualize commercial drivers' health and safety risks as multilayered networks centered on the WLE-CD and network relational patterns and topological properties-that is, arrangement, connections, and relationships among network components-that largely govern risk dynamics; and (d) elucidate how integrative exposome and network-science-based innovations can contribute to a more comprehensive understanding of commercial drivers' chronic disease and injury risk dynamics. Development, validation, and proliferation of this emerging discourse can move commercial driving epidemiology to the frontier of science with implications for policy, action, other working populations, and population health at large.

Practical cooling interventions for preventing heat strain in indoor factory workers in Thailand.

BACKGROUND: Occupational heat stress, exacerbated by factors such as climate change and insufficient cooling solutions, endangers the health and productivity of workers, especially in low-resource workplaces. OBJECTIVE: To evaluate the effectiveness of two cooling strategies in reducing physiological strain and productivity of piece-rate workers over a 9-h work shift in a southern Thailand sawmill. METHODS: In a crossover randomized control trial design, 12 (33 ± 7 y; 1.58 ± 0.05 m; 51 ± 9 kg; n = 5 females) medically screened sawmill workers were randomly allocated into three groups comprising an established phase change material vest (VEST), an on-site combination cooling oasis (OASIS) (i.e., hydration, cold towels, fans, water dousing), and no cooling (CON) across 3 consecutive workdays. Physiological strain was measured via core temperature telemetry and heart rate monitoring. Productivity was determined by counting the number of pallets of wood sorted, stacked, and stowed each day. RESULTS: Relative to CON, OASIS lowered core temperature by 0.25°C [95% confidence interval = 0.24, 0.25] and heart rate by 7 bpm [6, 9] bpm, compared to 0.17°C [0.17, 0.18] and 10 [9,12] bpm reductions with VEST. It was inconclusive whether productivity was statistically lower in OASIS compared to CON (mean difference [MD] = 2.5 [-0.2, 5.2]), and was not statistically different between VEST and CON (MD = 1.4 [-1.3, 4.1]). CONCLUSIONS: Both OASIS and VEST were effective in reducing physiological strain compared to no cooling. Their effect on productivity requires further investigation, as even small differences between interventions could lead to meaningful disparities in piece-rate worker earnings over time.

Utility of a Neuromuscular Activation Exercise Protocol on Surgeon Posture.

BACKGROUND: Surgeons are at risk for musculoskeletal disorders from ergonomic strain in the operating room. These deficits may stem from neuromuscular control deficits. Neuromuscular activation exercises (NMEs) may strengthen the brain-muscle connection. This study aimed to assess the utility of a surgeon-oriented NME protocol on posture. METHODS: Surgeons, operating room staff, and medical students completed a professionally established NME routine. An electronic application, PostureScreen®, assessed participants' posture. A long-term cohort was assessed before and after a 2 to 6-week routine. A short-term cohort was assessed immediately before and after completion. All participants additionally completed a postintervention survey. RESULTS: After intervention, the short-term cohort (n = 47) had significantly reduced frontal and sagittal postural deviation (P < 0.05). A significant decrease in effective head weight was additionally demonstrated with decreased neck flexion and increased cerebral-cervical symmetry (P < 0.05).The long-term cohort (n = 6) showed a significant postintervention decrease in lateral and anterior shoulder translation (P < 0.05). Total anterior translational deviations demonstrated trend-level decrease (P = 0.078). This demonstrates that after intervention, participants' shoulders were more centered with the spine as opposed to shifted right or left. Survey results showed participants favored exercises that immediately brought relief of tension. CONCLUSIONS: A decrease in postural deviations associated with NME in both cohorts demonstrates NME as a potential mechanism to protect surgeon musculoskeletal health and improve well-being. Survey results demonstrate areas of refinement for NME protocol design.

Risk assessment of healthcare workers' exposure to physical load in relation to patient handling and movement: a feasibility study of the instrument TilThermometer.

BACKGROUND: Work-related musculoskeletal disorders are common among healthcare workers (HCWs) but might be prevented by risk assessment and further promotion of occupational safety and health. The aim of this study was to investigate if the risk assessment instrument TilThermometer can be used to identify risk profiles of physical exposure in HCWs working with patient handling and movement (PHM). Further aims were to describe HCWs' perceptions and experiences of using the TilThermometer. METHODS: This feasibility study has a mixed design methodology. In total, 54 HCWs from 17 Swedish care units participated and performed risk assessments with the TilThermometer. Data collected from the risk assessments were used to identify risk profiles of physical exposure. HCWs' experiences of using the TilThermometer were collected from activity logs and analysed qualitatively. Three questionnaires were used to assess perceived acceptability, appropriateness, and feasibility of the risk assessment, and eight study specific questions were used for perceived usefulness. RESULTS: The TilThermometer was used at the care units by assessing each care recipient, and when compiling the data at a group level, a summarized risk profile for the care unit could be provided. Risk for physical exposure was reported as high in two work tasks; no care unit used the high-low adjustable seat when showering care recipients sitting down, and 13% used the recommended assistive devices when putting compression stockings on. However, 99% used high-low adjustable assistive devices when caring and bathing care recipients lying down. TilThermometer was described as easy to use, enabling team reflections and providing an overview of the care units' recipients and workload, but difficulties in categorizing for mobility groups were also reported. The TilThermometer was, on a five-point scale, perceived as acceptable (mean 3.93), appropriate (mean 3.9), and feasible (mean 3.97). These scores are in line with questions evaluating usefulness. CONCLUSION: The risk assessment provided risk profiles with potential to contribute to care units' development of a safe patient handling and movement practice. The findings suggest that the TilThermometer can be used to assess risks for physical exposure in relation to patient handling and movement in care units at hospital and nursing homes.

Exertional rhabdomyolysis among active component members of the U.S. Armed Forces, 2019-2023.

A largely preventable condition, exertional rhabdomyolysis persists as an occupational hazard of military training and operations, especially in high heat environments among individuals exerting themselves to their physical endurance limits. During the 5-year surveillance period of this study, unadjusted incidence rates of exertional rhabdomyolysis per 100,000 person-years among U.S. active component service members fluctuated, reaching a low of 38.0 cases in 2020 and peaking at 40.5 cases in 2023. The rate in 2020 constituted a decline of 3.8% from the rate in 2019 (39.5 cases). Beginning in 2020, incidence rates per 100,000 person-years gradually increased, by 1.8% in 2021 (38.7 cases), 5.3% in 2022 (40.0 cases), and 6.6% in 2023 (40.5 cases). Consistent with prior reports, subgroup-specific crude rates in 2023 were highest among men, those less than 20 years old, non-Hispanic Black service members, Marine Corps or Army members, and those in combat-specific and 'other' occupations. Recruits experienced the highest rates of exertional rhabdomyolysis during each year, with incidence rates 6 to 10 times greater than all other service members.

Heat exhaustion and heat stroke among active component members of the U.S. Armed Forces, 2019-2023.

The most serious types of heat illnesses, heat exhaustion and heat stroke, are occupational hazards associated with many of the military's training and operational environments. These illnesses can typically be prevented by appropriate situational awareness, risk management strategies, along with effective countermeasures. In 2023, the crude incidence of heat stroke and heat exhaustion were 31.7 and 172.7 cases per 100,000 person-years, respectively. The rates of incident heat stroke declined during the 2019 to 2023 surveillance period, but rates of incident heat exhaustion increased over the same period. In 2023, higher rates of heat stroke were observed among male service members compared to their female counterparts, and female service members experienced higher rates of heat exhaustion compared to male personnel. Heat illness rates were also higher among those younger than age 20, Marine Corps and Army service members, non-Hispanic Black service members, and recruits. Leaders, training cadres, and supporting medical and safety personnel must inform their subordinate and supported service members of heat illness risks, preventive measures, early signs and symptoms of illness, and appropriate interventions.

ERRATUM: Musculoskeletal pain among nursing professionals in material and sterilization centers.

[This corrects the article doi: 10.1590/1980-220X-REEUSP-2023-0019en] [This corrects the article doi: 10.1590/1980-220X-REEUSP-2023-0019pt].

Effect of exercise given to factory workers with ergonomics training on pain and functionality: A randomized controlled trial.

BACKGROUND: Exercise and manual therapy are used with pharmacological interventions to manage low back pain and prevent work-related musculoskeletal disorders. However, the potential benefits of incorporating exercise and ergonomics training for factory workers experiencing low back pain have not been definitively established. OBJECTIVE: The objective of this study was to assess the impact of ergonomics training with exercises on pain, functionality, sleep, and fatigue among factory employees experiencing low back pain. METHODS: This research was conducted as a randomized controlled trial involving workers with back pain employed in a plastic molding factory in Gebze, Kocaeli. Both groups received ergonomics training, but only the experimental group was given exercise training inclusive of stretching and core stabilization exercises. The workers in the experimental group were instructed to perform the exercises regularly for three days a week over a period of eight weeks. The McGill Pain Questionnaire (MPQ), the Visual Analogue Scale (VAS), the Fatigue Severity Scale (FSS), the Pittsburgh Sleep Quality Index (PSQI), and the Oswestry Disability Index (ODI) were used for pre-and post-treatment assessment. RESULTS: The ODI, FSS, PSQI, and MPQ scores were significantly reduced in both groups. In the intergroup comparison, the exercise group showed a significantly greater decrease in all test scores compared to the control group. CONCLUSION: The exercise group showed a statistically significant decrease in ODI, FSS, MPQ, and PSQI scores compared to the control group. This study demonstrated that exercise is a more effective practice than ergonomic training for factory workers suffering from chronic low back pain.

Assessment of the musculoskeletal discomfort scale for upper limb among workers in inner Brazil.

BACKGROUND: Work-related musculoskeletal disorders for upper limbs (UL-WMSDs) form a complex of occupational diseases common to many professions worldwide. UL-WMSDs are manifested in most cases by pain, resulting in musculoskeletal discomfort. OBJECTIVE: This research aimed to evaluate the perception of musculoskeletal discomfort in workers from the interior of the Brazilian states of Alagoas and Bahia through the construction of a scale to assess musculoskeletal discomfort for upper limb. METHODS: The discomfort assessment scale was constructed from self-reported pain symptoms by 420 workers from the inner regions of the Brazilian states of Alagoas and Bahia. The reliability and dimensionality of the collected data were analyzed by McDonald's Omega and exploratory factor analysis, respectively. Item Response Theory (IRT) was used to create parameters for the discomfort scale. RESULTS: The musculoskeletal discomfort metric was constructed from the workers' response with six levels (varying from minimum discomfort to maximum discomfort). At the lowest level of the scale, workers indicated symptoms in the shoulders and wrists were rare. At the highest level of the scale, daily pain symptoms are reported in all regions of the upper limbs. The shoulders are the last region to develop extreme pain symptoms. CONCLUSION: The metric was created to present satisfactory psychometric properties and capable measurement of the workers' level of musculoskeletal discomfort based on self-reported pain symptoms. Therefore, the metric can support measuring discomfort, contributing to decisions that improve a healthier occupational environment for the worker.

Assessment and evaluation of work-related musculoskeletal disorders among nuclear medicine professionals in India: A cross-sectional study.

BACKGROUND: Musculoskeletal disorders (MSDs) are a severe occupational health issue among medical radiation practitioners. It is mostly linked to personal protective wear, working posture, tools employed and ergonomics. OBJECTIVE: To assess and evaluate the musculoskeletal disorders among nuclear medicine professionals (NMP) in India. METHODS: An online survey was distributed to 455 NMP throughout India between November 2021 and March 2022 covering the demographic characteristics and questions for evaluation of musculoskeletal symptoms using the Standardized Nordic Musculoskeletal Questionnaire (NMQ). Participants with any pre-existing musculoskeletal disorder or trauma were excluded. Descriptive statistics summarized the data from the demographics, discomfort, aches and work-related musculoskeletal injuries. Chi-square test was used to examine the association between the obtained values. RESULTS: 91 out of 124 respondents were included based on the inclusion and exclusion criteria. Results shows that there is a significant association between the height of the individual and neck pain, body mass index and elbows pain, age and low back pain, experience in the current work and upper back pain, the weight of the individual and knee pain, use of mobile lead screens and shoulder pain, use of gonad shield, trouble in the ankles and use of lead screens, and QC phantoms for gamma camera / PET and wrists/hands pain. CONCLUSION: Work-related musculoskeletal disorders among NMP are resulting from factors of individual demographic variables (such as age, height, weight, body mass index), years of experience at the current workplace and of using instruments in their work area.

Study of musculoskeletal disorders risk factors and discomfort in sculptors in the north of Mexico.

BACKGROUND: The sculpting craft must adopt awkward postures that lead to musculoskeletal disorders (MSDs). OBJECTIVE: This study investigated the prevalence of musculoskeletal discomfort (MD) and its associations with postural risk factors, demographics, and work characteristics among sculptors. They were determined the differences between MDs during the weeks of the study. METHODS: A longitudinal study was conducted; MD was investigated using the Cornell Musculoskeletal Discomfort Questionnaire (CMDQ). Posture was assessed using the Rapid Upper Limb Assessment method (RULA). Multivariate logistic regression (MLR) models analyzed associations with different factors. ANOVA was used to test for differences in MD prevalence. RESULTS: The analysis included 585 responses by body region. The prevalence of MD was high in the lower and upper limbs among sculptors (67.6%), with the lower back, upper arm, neck, and knees being the four most affected regions. Gender (female) (OR = 2.15), marital status (married) (OR = 1.80), health risk (obesity), the dual of a secondary job (OR = 1.94), job stress (OR = 2.10), duration of work (OR = 2.01), and difficulty keeping up with work (OR = 2.00) were significant predictors contributing to the occurrence of MD in different body regions. Only shoulder MD prevalence showed significant differences between study weeks. CONCLUSIONS: Sculptors suffer from MD. Demographic and work characteristic factors influence MD prevalence. Postural training, improved adaptation of work organization, and intervention guidance on ergonomic risks may reduce the prevalence of MD and the risk of MSDs in this population.

The OCCHLTH Mnemonic-Construction and Content of a Tool for Increasing Awareness of Occupational Illness and Injury.

INTRODUCTION: Unidentified or nonmitigated occupational illnesses and injuries can complicate disease management. The "occupational health" (OCCHLTH) mnemonic aims to raise awareness of work-related exposures and associated illnesses and injuries. METHODS: Occupational safety and health history-taking elements were combined with peer-reviewed information [from the PubMed database (first review January 1, 2000, to February 8, 2016; updated to February 8, 2021)] about workplace exposure-outcome associations to create the mnemonic. RESULTS: Seven components constitute the OCCHLTH mnemonic. Literature results support its categories and subcategories. Three components represent symptom onset and health conditions. Four represent occupational exposures. Evaluating published occupational illness cases explored mnemonic applicability. CONCLUSIONS: Awareness of occupational risk factors can affect clinical decision-making. The OCCHLTH mnemonic encourages consideration of occupational causes of illness and injury to optimize patient care. Further evaluation of the utility of the OCCHLTH mnemonic is needed.

Hearing protection field attenuation estimation systems and associated training for reducing workers' exposure to noise.

BACKGROUND: Global Burden of Disease studies identify hearing loss as the third leading cause of years lived with a disability. Their estimates point to large societal and individual costs from unaddressed hearing difficulties. Workplace noise is an important modifiable risk factor; if addressed, it could significantly reduce the global burden of disease. In practice, providing hearing protection devices (HPDs) is the most common intervention to reduce noise exposure at work. However, lack of fit of HPDs, especially earplugs, can greatly limit their effectiveness. This may be the case for 40% of users. Testing the fit and providing instructions to improve noise attenuation might be effective. In the past two decades, hearing protection fit-test systems have been developed and evaluated in the field. They are called field attenuation estimation systems. They measure the noise attenuation obtained by individual workers using HPDs. If there is a lack of fit, instruction for better fit is provided, and may lead to better noise attenuation obtained by HPDs. OBJECTIVES: To assess: (1) the effects of field attenuation estimation systems and associated training on the noise attenuation obtained by HPDs compared to no instruction or to less instruction in workers exposed to noise; and (2) whether these interventions promote adherence to HPD use. SEARCH METHODS: We used CENTRAL, MEDLINE, five other databases, and two trial registers, together with reference checking, citation searching, and contact with study authors to identify studies. We imposed no language or date restrictions. The latest search date was February 2024. SELECTION CRITERIA: We included randomised controlled trials (RCTs), cluster-RCTs, controlled before-after studies (CBAs), and interrupted time-series studies (ITSs) exploring HPD fit testing in workers exposed to noise levels of more than 80 A-weighted decibels (or dBA) who use hearing protection devices. The unit 'dBA' reports on the use of a frequency-weighting filter to adjust sound measurement results to better reflect how human ears process sound. The outcome noise attenuation had to be measured either as a personal attenuation rating (PAR), PAR pass rate, or both. PAR pass rate is the percentage of workers who passed a pre-established level of sufficient attenuation from their HPDs, identified on the basis of their individual noise exposure. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed study eligibility, risk of bias, and extracted data. We categorised interventions as fit testing of HPDs with instructions at different levels (no instructions, simple instructions, and extensive instructions). MAIN RESULTS: We included three RCTs (756 participants). We did not find any studies that examined whether fit testing and training contributed to hearing protector use, nor any studies that examined whether age, gender, or HPD experience influenced attenuation. We would have included any adverse effects if mentioned by the trial authors, but none reported them. None of the included studies blinded participants; two studies blinded those who delivered the intervention. Effects of fit testing of HPDs with instructions (simple or extensive) versus fit testing of HPDs without instructions Testing the fit of foam and premoulded earplugs accompanied by simple instructions probably does not improve their noise attenuation in the short term after the test (1-month follow-up: mean difference (MD) 1.62 decibels (dB), 95% confidence interval (CI) -0.93 to 4.17; 1 study, 209 participants; 4-month follow-up: MD 0.40 dB, 95% CI -2.28 to 3.08; 1 study, 197 participants; both moderate-certainty evidence). The intervention probably does not improve noise attenuation in the long term (MD 0.15 dB, 95% CI -3.44 to 3.74; 1 study, 103 participants; moderate-certainty evidence). Fit testing of premoulded earplugs with extensive instructions on the fit of the earplugs may improve their noise attenuation at the immediate retest when compared to fit testing without instructions (MD 8.34 dB, 95% CI 7.32 to 9.36; 1 study, 100 participants; low-certainty evidence). Effects of fit testing of HPDs with extensive instructions versus fit testing of HPDs with simple instructions Fit testing of foam earplugs with extensive instructions probably improves their attenuation (MD 8.62 dB, 95% CI 6.31 to 10.93; 1 study, 321 participants; moderate-certainty evidence) and also the pass rate of sufficient attenuation (risk ratio (RR) 1.75, 95% CI 1.44 to 2.11; 1 study, 321 participants; moderate-certainty evidence) when compared to fit testing with simple instructions immediately after the test. This is significant because every 3 dB decrease in noise exposure level halves the sound energy entering the ear. No RCTs reported on the long-term effectiveness of the HPD fit testing with extensive instructions. AUTHORS' CONCLUSIONS: HPD fit testing accompanied by simple instructions probably does not improve noise attenuation from foam and premoulded earplugs. Testing the fit of foam and premoulded earplugs with extensive instructions probably improves attenuation and PAR pass rate immediately after the test. The effects of fit testing associated with training to improve attenuation may vary with types of HPDs and training methods. Better-designed trials with larger sample sizes are required to increase the certainty of the evidence.

The influence of occupational heat stress on serum inflammatory cytokines among traditional bakery workers in Iran.

Heat exposure exceeding the ISO7243:1989 standard limit can contribute to health problems among employees in a variety of workplaces. Ignoring heat standard requirements in hot working conditions such as bakeries results in physiologic and health problems, as well as an elevated risk of later illnesses. In this analytical case-control study, the serum levels of four inflammatory factors (interleukin-1 beta, interleukin-6, tumor necrosis factor-α, and C-reactive protein) were assessed using an enzyme-linked immunosorbent assay. 105 male artisan bakers (in four job classifications in bakeries and staff) were compared based on demographic characteristics and inflammatory factors. The findings of the study showed correlations between serum interleukin-1ß, interleukin-6, and C-reactive protein levels and thermal exposure in the occupational environment and employment type. Moreover, some differences in serum level of interleukin-1ß and job type were observed. Heat overexposure affected the increase of interleukin-1ß and C-reactive protein secretion. As a result of years of working in high-temperature conditions, inflammation can lead to subsequent diseases in workers. To protect their health from this occupational hazard, additional safeguards are needed. Our recommendations could also be applied to overly hot work environments that may cause heat stress in workers.