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Journal of Environmental Health Science... Jun 2024Air pollution is a major cause of specific deaths worldwide. This review article aimed to investigate the results of cohort studies for air pollution connected with the... (Review)
Review
UNLABELLED
Air pollution is a major cause of specific deaths worldwide. This review article aimed to investigate the results of cohort studies for air pollution connected with the all-cause, cardio-respiratory, and lung cancer mortality risk by performing a meta-analysis. Relevant cohort studies were searched in electronic databases (PubMed/Medline, Web of Science, and Scopus). We used a random effect model to estimate the pooled relative risks (RRs) and their 95% CIs (confidence intervals) of mortality. The risk of bias for each included study was also assessed by Office of Health Assessment and Translation (OHAT) checklists. We applied statistical tests for heterogeneity and sensitivity analyses. The registration code of this study in PROSPERO was CRD42023422945. A total of 88 cohort studies were eligible and included in the final analysis. The pooled relative risk (RR) per 10 μg/m increase of fine particulate matter (PM) was 1.080 (95% CI 1.068-1.092) for all-cause mortality, 1.058 (95% CI 1.055-1.062) for cardiovascular mortality, 1.066 (95%CI 1.034-1.097) for respiratory mortality and 1.118 (95% CI 1.076-1.159) for lung cancer mortality. We observed positive increased associations between exposure to PM, PM, black carbon (BC), and nitrogen dioxide (NO) with all-cause, cardiovascular and respiratory diseases, and lung cancer mortality, but the associations were not significant for nitrogen oxides (NOx), sulfur dioxide (SO) and ozone (O). The risk of mortality for males and the elderly was higher compared to females and younger age. The pooled effect estimates derived from cohort studies provide substantial evidence of adverse air pollution associations with all-cause, cardiovascular, respiratory, and lung cancer mortality.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s40201-024-00900-6.
PubMed: 38887768
DOI: 10.1007/s40201-024-00900-6 -
Environment International Jun 2024To inform radiofrequency electromagnetic field (RF-EMF) exposure guidelines the World Health Organization (WHO) is bringing together evidence on RF-EMF in relation to...
BACKGROUND
To inform radiofrequency electromagnetic field (RF-EMF) exposure guidelines the World Health Organization (WHO) is bringing together evidence on RF-EMF in relation to health outcomes prioritised for evaluation by experts in this field. Given this, a network of topic experts and methodologists have conducted a series of systematic reviews collecting, assessing, and synthesising data of relevance to these guidelines. Here we present a systematic review of the effect of RF-EMF exposure on adverse pregnancy outcomes in human observational studies which follows the WHO handbook for guideline development and the COSTER conduct guidelines.
METHODS
We conducted a broad, sensitive search for potentially relevant records within the following bibliographic databases: MEDLINE; Embase; and the EMF Portal. Grey literature searches were also conducted through relevant databases (including OpenGrey), organisational websites and via consultation of RF-EMF experts. We included quantitative human observational studies on the effect of RF-EMF exposure in adults' preconception or pregnant women on pre-term birth, small for gestational age (SGA; associated with intrauterine growth restriction), miscarriage, stillbirth, low birth weight (LBW) and congenital anomalies. In blinded duplicate, titles and abstracts then full texts were screened against eligibility criteria. A third reviewer gave input when consensus was not reached. Citation chaining of included studies was completed. Two reviewers' data extracted and assessed included studies for risk of bias using the Office of Health Assessment and Translation (OHAT) tool. Random effects meta-analyses of the highest versus the lowest exposures and dose-response meta-analysis were conducted as appropriate and plausible. Two reviewers assessed the certainty in each body of evidence using the OHAT GRADE tool.
RESULTS
We identified 18 studies in this review; eight were general public studies (with the general public as the population of interest) and 10 were occupational studies (with the population of interest specific workers/workforces). General public studies. From pairwise meta-analyses of general public studies, the evidence is very uncertain about the effects of RF-EMF from mobile phone exposure on preterm birth risk (relative risk (RR) 1.14, 95% confidence interval (CI): 0.97-1.34, 95% prediction interval (PI): 0.83-1.57; 4 studies), LBW (RR 1.14, 95% CI: 0.96-1.36, 95% PI: 0.84-1.57; 4 studies) or SGA (RR 1.13, 95% CI: 1.02-1.24, 95% PI: 0.99-1.28; 2 studies) due to very low-certainty evidence. It was not feasible to meta-analyse studies reporting on the effect of RF-EMF from mobile phone exposure on congenital anomalies or miscarriage risk. The reported effects from the studies assessing these outcomes varied and the studies were at some risk of bias. No studies of the general public assessed the impact of RF-EMF exposure on stillbirth. Occupational studies. In occupational studies, based on dose-response meta-analyses, the evidence is very uncertain about the effects of RF-EMF amongst female physiotherapists using shortwave diathermy on miscarriage due to very low-certainty evidence (OR 1.02 95% CI 0.94-1.1; 2 studies). Amongst offspring of female physiotherapists using shortwave diathermy, the evidence is very uncertain about the effects of RF-EMF on the risk of congenital malformations due to very low-certainty evidence (OR 1.4, 95% CI 0.85 to 2.32; 2 studies). From pairwise meta-analyses, the evidence is very uncertain about the effects of RF-EMF on the risk of miscarriage (RR 1.06, 95% CI 0.96 to 1.18; very low-certainty evidence), pre-term births (RR 1.19, 95% CI 0.32 to 4.37; 3 studies; very low-certainty evidence), and low birth weight (RR 2.90, 95% CI: 0.69 to 12.23; 3 studies; very low-certainty evidence). Results for stillbirth and SGA could not be pooled in meta-analyses. The results from the studies reporting these outcomes were inconsistent and the studies were at some risk of bias.
DISCUSSION
Most of the evidence identified in this review was from general public studies assessing localised RF-EMF exposure from mobile phone use on female reproductive outcomes. In occupational settings, each study was of heterogenous whole-body RF-EMF exposure from radar, short or microwave diathermy, surveillance and welding equipment and its effect on female reproductive outcomes. Overall, the body of evidence is very uncertain about the effect of RF-EMF exposure on female reproductive outcomes. Further prospective studies conducted with greater rigour (particularly improved accuracy of exposure measurement and using appropriate statistical methods) are required to identify any potential effects of RF-EMF exposure on female reproductive outcomes of interest.
PubMed: 38880062
DOI: 10.1016/j.envint.2024.108816 -
Environment International Jun 2024The World Health Organization (WHO) is bringing together evidence on radiofrequency electromagnetic field (RF-EMF) exposure in relation to health outcomes, previously...
BACKGROUND
The World Health Organization (WHO) is bringing together evidence on radiofrequency electromagnetic field (RF-EMF) exposure in relation to health outcomes, previously identified as priorities for research and evaluation by experts in the field, to inform exposure guidelines. A suite of systematic reviews have been undertaken by a network of topic experts and methodologists to collect, assess and synthesise data relevant to these guidelines. Following the WHO handbook for guideline development and the COSTER conduct guidelines, we systematically reviewed the evidence on the potential effects of RF-EMF exposure on male fertility in human observational studies.
METHODS
We conducted a broad and sensitive search for potentially relevant records within the following bibliographic databases: MEDLINE; Embase; Web of Science and EMF Portal. We also conducted searches of grey literature through relevant databases including OpenGrey, and organisational websites and consulted RF-EMF experts. We hand searched reference lists of included study records and for citations of these studies. We included quantitative human observational studies on the effect of RF-EMF exposure in adult male participants on infertility: sperm concentration; sperm morphology; sperm total motility; sperm progressive motility; total sperm count; and time to pregnancy. Titles and abstracts followed by full texts were screened in blinded duplicate against pre-set eligibility criteria with consensus input from a third reviewer as required. Data extraction from included studies was completed by two reviewers, as was risk of bias assessment using the Office of Health Assessment and Translation (OHAT) tool. We conducted a dose-response meta-analysis as possible and appropriate. Certainty of the evidence was assessed by two reviewers using the OHAT GRADE tool with input from a third reviewer as required.
RESULTS
We identified nine studies in this review; seven were general public studies (with the general public as the population of interest) and two were occupational studies (with specific workers/workforces as the population of interest). General public studies. Duration of phone use: The evidence is very uncertain surrounding the effects of RF-EMF on sperm concentration (10/6 mL) (MD (mean difference) per hour of daily phone use 1.6 10/mL, 95 % CI -1.7 to 4.9; 3 studies), sperm morphology (MD 0.15 percentage points of deviation of normal forms per hour, 95 % CI -0.21 to 0.51; 3 studies), sperm progressive motility (MD -0.46 percentage points per hour, 95 % CI -1.04 to 0.13; 2 studies) and total sperm count (MD per hour -0.44 10/ejaculate, 95 % CI -2.59 to 1.7; 2 studies) due to very low-certainty evidence. Four additional studies reported on the effect of mobile phone use on sperm motility but were unsuitable for pooling; only one of these studies identified a statistically significant effect. All four studies were at risk of exposure characterisation and selection bias; two of confounding, selective reporting and attrition bias; three of outcome assessment bias and one used an inappropriate statistical method. Position of phone: There may be no or little effect of carrying a mobile phone in the front pocket on sperm concentration, total count, morphology, progressive motility or on time to pregnancy. Of three studies reporting on the effect of mobile phone location on sperm total motility and, or, total motile count, one showed a statistically significant effect. All three studies were at risk of exposure characterisation and selection bias; two of confounding, selective reporting and attrition bias; three of outcome assessment bias and one used inappropriate statistical method. RF-EMF Source: One study indicates there may be little or no effect of computer or other electric device use on sperm concentration, total motility or total count. This study is at probably high risk of exposure characterisation bias and outcome assessment bias. Occupational studies. With only two studies of occupational exposure to RF-EMF and heterogeneity in the population and exposure source (technicians exposed to microwaves or seamen exposed to radar equipment), it was not plausible to statistically pool findings. One study was at probably or definitely high risk of bias across all domains, the other across domains for exposure characterisation bias, outcome assessment bias and confounding.
DISCUSSION
The majority of evidence identified was assessing localised RF-EMF exposure from mobile phone use on male fertility with few studies assessing the impact of phone position. Overall, the evidence identified is very uncertain about the effect of RF-EMF exposure from mobile phones on sperm outcomes. One study assessed the impact of other RF-EMF sources on male fertility amongst the general public and two studies assessed the impact of RF-EMF exposure in occupational cohorts from different sources (radar or microwave) on male fertility. Further prospective studies conducted with greater rigour (in particular, improved accuracy of exposure measurement and appropriate statistical method use) would build the existing evidence base and are required to have greater certainty in any potential effects of RF-EMF on male reproductive outcomes. Prospero Registration: CRD42021265401 (SR3A).
PubMed: 38880061
DOI: 10.1016/j.envint.2024.108817 -
Environment International Jun 2024We aimed to assess evidence of long-term effects of exposure to radiofrequency (RF) electromagnetic fields (EMF) on indicators of cognition, including domains of... (Meta-Analysis)
Meta-Analysis
BACKGROUND
We aimed to assess evidence of long-term effects of exposure to radiofrequency (RF) electromagnetic fields (EMF) on indicators of cognition, including domains of learning and memory, executive function, complex attention, language, perceptual motor ability and social cognition, and of an exposure-response relationship between RF-EMF and cognition.
METHODS
We searched PubMed, Embase, PsycInfo and the EMF-Portal on September 30, 2022 without limiting by date or language of publication. We included cohort or case-control studies that evaluated the effects of RF exposure on cognitive function in one or more of the cognitive domains. Studies were rated for risk of bias using the OHAT tool and synthesised using fixed effects meta-analysis. We assessed the certainty of the evidence using the GRADE approach and considered modification by OHAT for assessing evidence of exposures.
RESULTS
We included 5 studies that reported analyses of data from 4 cohorts with 4639 participants consisting of 2808 adults and 1831 children across three countries (Australia, Singapore and Switzerland) conducted between 2006 and 2017. The main source of RF-EMF exposure was mobile (cell) phone use measured as calls per week or minutes per day. For mobile phone use in children, two studies (615 participants) that compared an increase in mobile phone use to a decrease or no change were included in meta-analyses. Learning and memory. There was little effect on accuracy (mean difference, MD -0.03; 95% CI -0.07 to 0.02) or response time (MD -0.01; 95% CI -0.04 to 0.02) on the one-back memory task; and accuracy (MD -0.02; 95%CI -0.04 to 0.00) or response time (MD -0.01; 95%CI -0.04 to 0.03) on the one card learning task (low certainty evidence for all outcomes). Executive function. There was little to no effect on the Stroop test for the time ratio ((B-A)/A) response (MD 0.02; 95% CI -0.01 to 0.04, very low certainty) or the time ratio ((D-C)/C) response (MD 0.00; 95% CI -0.06 to 0.05, very low certainty), with both tests measuring susceptibility to interference effects. Complex attention. There was little to no effect on detection task accuracy (MD 0.02; 95% CI -0.04 to 0.08), or response time (MD 0.02;95% CI 0.01 to 0.03), and little to no effect on identification task accuracy (MD 0.00; 95% CI -0.04 to 0.05) or response time (MD 0.00;95% CI -0.01 to 0.02) (low certainty evidence for all outcomes). No other cognitive domains were investigated in children. A single study among elderly people provided very low certainty evidence that more frequent mobile phone use may have little to no effect on the odds of a decline in global cognitive function (odds ratio, OR 0.81; 95% CI 0.42 to 1.58, 649 participants) or a decline in executive function (OR 1.07; 95% CI 0.37 to 3.05, 146 participants), and may lead to a small, probably unimportant, reduction in the odds of a decline in complex attention (OR 0.67;95%CI 0.27 to 1.68, 159 participants) and a decline in learning and memory (OR 0.75; 95% CI 0.29 to 1.99, 159 participants). An exposure-response relationship was not identified for any of the cognitive outcomes.
DISCUSSION
This systematic review and meta-analysis found only a few studies that provided very low to low certainty evidence of little to no association between RF-EMF exposure and learning and memory, executive function and complex attention. None of the studies among children reported on global cognitive function or other domains of cognition. Only one study reported a lack of an effect for all domains in elderly persons but this was of very low certainty evidence. Further studies are needed to address all types of populations, exposures and cognitive outcomes, particularly studies investigating environmental and occupational exposure in adults. Future studies also need to address uncertainties in the assessment of exposure and standardise testing of specific domains of cognitive function to enable synthesis across studies and increase the certainty of the evidence.
OTHER
This review was partially funded by the WHO radioprotection programme and prospectively registered on PROSPERO CRD42021257548.
Topics: Humans; Cognition; Radio Waves; Electromagnetic Fields; Observational Studies as Topic; Child; Cell Phone; Environmental Exposure; Adult; Memory
PubMed: 38821015
DOI: 10.1016/j.envint.2024.108779 -
Indian Journal of Occupational and... 2024Today, mobile phones are one of the most common devices emitting electromagnetic radiation and are available to more than seven billion people in different age groups... (Review)
Review
Today, mobile phones are one of the most common devices emitting electromagnetic radiation and are available to more than seven billion people in different age groups around the world. The effects of electromagnetic radiation on biological systems have been studied for several years. In this systematic review to find relevant articles, international databases such as Google Scholar, PubMed, Scopus, Science Direct, Web of Science, and Cochrane were used since 2007-2022 by selecting appropriate keywords. The result revealed that exposure to cell phone radiation can lead to disturb in the metabolic activity of the cerebellum by increasing the migration of granulosa cells, decrease the water around the fetus in pregnant women, decrease in the number of blood plates, increasing levels of ALT and AST that they are the key biomarkers of liver damage, decrease of phagocytosis and induced apoptosis of neutrophils, changes at the level of glucose and even at the microscopic level of pancreas this may be a predisposing factor for diabetes, increment in tissue temperature in all depth of the brain tissue, EMF increase the volume, weight, and atresia follicles of the ovaries of the children, also it can cause oxidative stress, DNA fragmentation, etc. Mobile phone radiation is harmful and depends on its intensity, frequency, wave type, and exposure duration. It can cause different biological effects in humans. Due to the uncertainty of the results and mechanism of the effect of these waves, research in this field is still ongoing.
PubMed: 38783888
DOI: 10.4103/ijoem.ijoem_89_23 -
Indian Journal of Occupational and... 2024Climate change increases heat stress exposure and occupational heat strain in tropical and subtropical regions with generally hot-humid climate conditions. The present... (Review)
Review
Climate change increases heat stress exposure and occupational heat strain in tropical and subtropical regions with generally hot-humid climate conditions. The present systematic review was conducted to assess the effect of climate change on occupational heat strain among women workers. In this study, three main databases (PubMed, Scopus, and Web of Science) were searched to find relevant literature on climate change and its effects using subject headings and appropriate MeSh terms. This article has been written according to the PRISMA checklist. A total of 6,176 studies were identified for screening and 13 studies were eligible for data extraction. Scientific evidence reveals that there is an imprecise but positive relationship between climate change and occupational heat strain regarding women workers. Some complications associated with occupational heat strain among women workers include fatigue, discomfort, dehydration, reduced brain function, and loss of concentration. Climate change can lead to an increase in the occurrence of heat-related illnesses and the levels of injury risk. In addition, its adverse health effects on women workers are mentioned. This systematic study identifies key priorities for action to better characterize and understand how occupational heat strain among women workers may be associated with climate change events. Strong evidence indicates that climate change will continue to cause occupational heat strain among women workers. It is essential to implement preventive measures considering multidisciplinary strategies to reduce the adverse effects of climate change on women workers health in hot weather settings. This can limit the health risks and negative effects of climate change.
PubMed: 38783874
DOI: 10.4103/ijoem.ijoem_320_21 -
Environmental Research May 2024Recent reports suggest that benzene exposure may be associated with solid cancers, such as lung and bladder cancers. Instead, evidence on the association between benzene... (Review)
Review
Recent reports suggest that benzene exposure may be associated with solid cancers, such as lung and bladder cancers. Instead, evidence on the association between benzene and colorectal cancer (CRC) is sparse. Thus, we aimed to summarize current literature on the association between occupational benzene exposure and CRC. We searched Pubmed, Embase (through Ovid), and Scopus to retrieve cohort and nested case-control studies on the association between occupational benzene exposure and solid cancers. The search was initially completed in December 2022 and later updated in April 2024. We assessed quality of included studies using a modified version of Newcastle-Ottawa Scale. We computed pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) of CRC according to occupational benzene exposure, using the Paule-Mandel method. Twenty-eight studies were included in the meta-analysis. Most of them were conducted in Europe or North America (82.1%) and were industry-based (89.3%). Pooled RRs comparing workers exposed to benzene with those who were unexposed for incidence and mortality were 1.10 (95% CI: 1.06, 1.15) and 1.04 (95% CI: 0.97, 1.11) for CRC, 1.12 (95% CI: 1.01, 1.24) and 1.08 (95% CI: 0.99, 1.19) for colon cancer, and 1.04 (95% CI: 0.94, 1.14) and 1.05 (95% CI: 0.92, 1.19) for rectal cancer, respectively. Only one study supported the occurrence of a dose-response relationship between occupational benzene exposure and CRC, while others found no increase in risk according to dose of exposure or duration of employment. Our findings suggest that occupational benzene exposure may be associated with CRC. Further research with detailed assessment of individual-level exposure is warranted to confirm our results.
PubMed: 38782339
DOI: 10.1016/j.envres.2024.119213 -
Occupational Medicine (Oxford, England) Jun 2024Sarcoidosis is a rare, multisystem, inflammatory condition associated with the formation of granulomas. Diagnosis can be challenging because of non-specific symptoms... (Review)
Review
BACKGROUND
Sarcoidosis is a rare, multisystem, inflammatory condition associated with the formation of granulomas. Diagnosis can be challenging because of non-specific symptoms complicating epidemiological investigations of its aetiology. Despite research efforts, a review of the current state of the evidence is needed.
AIMS
To assess the evidence for an association between occupational exposures and the development of sarcoidosis. To determine if workers in any occupation are at a greater risk of developing sarcoidosis.
METHODS
This rapid review follows the methodology suggested by the World Health Organization. Two electronic databases were systematically searched until April 2022. The methodological quality of the studies was critically appraised, and a best-evidence approach was used to synthesize the results.
RESULTS
Titles and abstracts of 2916 articles were screened, with 67 full-text articles reviewed for eligibility. Among the 13 studies eligible for this review, none were of high quality (i.e. low risk of bias). Six studies exploring the association between sarcoidosis and a range of occupations and exposures, and one previous systematic review were of low quality reporting inconsistent findings. Six studies examined the risk of sarcoidosis associated with occupational silica exposure, two of which were of acceptable quality. Overall, the study methodologies and results were inadequate to support causal relationships.
CONCLUSIONS
There is limited evidence of acceptable methodological quality to assess the risk of sarcoidosis associated with occupational exposures. There is a growing body of research examining occupational exposure to silica and sarcoidosis. Additional high-quality confirmatory research is needed.
Topics: Humans; Occupational Exposure; Sarcoidosis; Occupational Diseases
PubMed: 38776441
DOI: 10.1093/occmed/kqae016 -
New Solutions : a Journal of... May 2024Workers' compensation systems aim to financially support injured workers. However, seeking compensation often leads to poorer physical and mental health outcomes. This...
Workers' compensation systems aim to financially support injured workers. However, seeking compensation often leads to poorer physical and mental health outcomes. This review examines previous studies to investigate the relationship between workers' compensation and mental health and self-harm outcomes. A three-tiered search strategy across five databases identified studies that examined workers' compensation claims as an exposure or risk factor, with outcomes related to mental health, self-harm and suicidality. Nine full-text studies were included; however, heterogeneity limited generalizability. Most studies supported an association between pursuing compensation and poorer mental health and self-harm outcomes. Some studies attributed this to specific aspects of the system such as justice perception and navigation of the claims system. Findings suggest an association between workers' compensation and mental health or self-harm outcomes. Inconclusive findings highlight the need for further research. Understanding the psychiatric impacts of pursuing compensation is crucial to help formulate a more accessible compensation system.
PubMed: 38767147
DOI: 10.1177/10482911241254836 -
The Cochrane Database of Systematic... May 2024Global 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... (Meta-Analysis)
Meta-Analysis Review
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.
Topics: Humans; Ear Protective Devices; Noise, Occupational; Hearing Loss, Noise-Induced; Randomized Controlled Trials as Topic; Occupational Exposure; Occupational Diseases
PubMed: 38757544
DOI: 10.1002/14651858.CD015066.pub2