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The article informs about the impact of job exposure matrix (JEM) specifications on the relationship between occupational silica exposure and lung cancer risk in community-based studies. Topics include the analysis of exposure-response relationships using different dimensions of SYN-JEM, with results indicating that including all dimensions yields the best model fit, particularly emphasizing the importance of quantitative job-specific estimates in the JEM.

OBJECTIVES: The quantitative job-exposure matrix SYN-JEM consists of various dimensions: job-specific estimates, region-specific estimates, and prior expert ratings of jobs by the semi-quantitative DOM-JEM. We analyzed the effect of different JEM dimensions on the exposure–response relationships between occupational silica exposure and lung cancer risk to investigate how these variations influence estimates of exposure by a quantitative JEM and associated health endpoints. METHODS: Using SYN-JEM, and alternative SYN-JEM specifications with varying dimensions included, cumulative silica exposure estimates were assigned to 16 901 lung cancer cases and 20 965 controls pooled from 14 international community-based case-control studies. Exposure–response relationships based on SYN-JEM and alternative SYN-JEM specifications were analyzed using regression analyses (by quartiles and log-transformed continuous silica exposure) and generalized additive models (GAM), adjusted for age, sex, study, cigarette pack-years, time since quitting smoking, and ever employment in occupations with established lung cancer risk. RESULTS: SYN-JEM and alternative specifications generated overall elevated and similar lung cancer odds ratios ranging from 1.13 (1st quartile) to 1.50 (4th quartile). In the categorical and log-linear analyses SYN-JEM with all dimensions included yielded the best model fit, and exclusion of job-specific estimates from SYN-JEM yielded the poorest model fit. Additionally, GAM showed the poorest model fit when excluding job-specific estimates. CONCLUSION: The established exposure–response relationship between occupational silica exposure and lung cancer was marginally influenced by varying the dimensions of SYN-JEM. Optimized modelling of exposure–response relationships will be obtained when incorporating all relevant dimensions, namely prior rating, job, time, and region. Quantitative job-specific estimates appeared to be the most prominent dimension for this general population JEM.

Objectives Industry- and occupation-based carcinogen exposure matrices play a pivotal role in preventing occupational cancer. While the Korean CARcinogen EXposure (K-CAREX) has been developed in recent years to assess exposure prevalence and intensity by industry, the feasibility of constructing an occupation-based exposure matrix remains unexplored. Hence, the objective of this study is to explore the potential of combining the nationwide work environment measurement database (WEMD) and the special health examination database (SHED) to develop a comprehensive occupation-based exposure matrix. Methods The WEMD provides information on airborne lead measurements, including industry codes, but it does not include data related to occupations. In contrast, the SHED contains information on both occupation and blood lead levels. By integrating these 2 databases, we attempted to assess airborne lead exposure levels by occupation. Additionally, we performed a rank correlation analysis to compare the airborne exposure levels with corresponding blood lead levels according to occupation. Results A total of 35 425 workers who both wore air samplers for lead and underwent special health examinations for lead were extracted between 2019 and 2021. An occupation-based exposure matrix was developed to evaluate the intensity of lead exposure across a range of occupations, encompassing 51 minor occupations and 70-unit occupations. Rank correlation analyses showed strong positive correlations between airborne lead and blood lead measurements according to occupation. Conclusions Our study findings suggest that combining 2 nationwide surveillance databases can be an effective approach for creating an occupation-based exposure matrix. However, our results also highlight several limitations that need to be addressed in future studies to improve the accuracy and reliability of such matrices. [ABSTRACT FROM AUTHOR]

We aimed to assess the association between occupational noise exposure and long-term hearing decline. This prospective cohort study used linear regression to investigate the association between occupational noise exposure and 20-year hearing decline, adjusted for important confounders. The Norwegian cohort (N = 4,448) participated in two population-based health studies with pure-tone audiometry; HUNT2 1996–1998 and HUNT4 2017–2019. Exposure assessments included a quantitative job exposure matrix (JEM) and questionnaires. The participants (40.2% men, 20–39 years at baseline) had a mean 20-year decline (3–6 kHz) of 11.3 ± 9.8 decibels (dB). There was a positive association between 20-year logarithmic average noise level (JEM-based, LEX,20y) and 20-year hearing decline among men. Compared with no exposure ≥80 dB during follow-up, minimum 5 years of exposure ≥85 dB (JEM-based) predicted 2.6 dB (95% CI: 0.2–5.0) larger 20-year decline for workers aged 30–39 years at baseline, and −0.2 dB (95% CI: −2.2 to 1.7) for workers aged 20–29 years. Combining JEM information with self-reported noise exposure data resulted in stronger associations. This large longitudinal study shows an association between JEM-based noise exposure level and increased 20-year hearing decline among men. Contrary to expectations, the associations were weaker among younger workers, which might reflect a latency period. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The etiology of testicular germ cell tumors (TGCT) is suspected to be related to prenatal environmental risk factors. Some solvents have potential endocrine disrupting or carcinogenic properties and may disrupt male genital development in utero. The aim of this study was to examine the association between parental occupational exposure to solvents and TGCT risk among their offspring. METHODS: A French nationwide case–control study, TESTIS included 454 TGCT cases and 670 controls frequency-matched on region and 5-year age strata. Participants were interviewed via telephone and provided information on parental occupations at birth. Job-exposure matrices (JEM) developed in the French Matgéné program were used to assign exposure to five petroleum-based solvents, five solvents or groups of oxygenated solvents, and five chlorinated solvents. Odds ratios (OR) for TGCT and 95% confidence intervals (CI) were estimated using conditional logistic regression, adjusting for TGCT risk factors. RESULTS: Occupational exposure to at least one solvent during the year of their son’s birth was 41% among fathers and 21% among mothers. Paternal exposure to at least one solvent showed OR 0.89 (95% CI 0.68–1.15). Exposure to perchloroethylene (OR 1.41, 95% CI 0.55–3.61), methylene chloride (OR 1.13, 95% CI 0.54–2.34) and diesel/kerosene/fuel oil (OR 1.17, 95% CI 0.80–1.73) disclosed OR >1 but with low precision. Our results suggest a possible modest increase in non-seminoma risk for sons whose fathers were highly exposed to trichloroethylene (OR 1.44, 95% CI 0.79–2.63). Maternal exposure to at least one solvent showed OR 0.90 (95% CI 0.65–1.24). When stratifying by birth year, men born in the 1970s experienced an increased TGCT risk following maternal exposure to fuels and petroleum-based solvents (OR 2.74, 95% CI 1.11–6.76). CONCLUSION: Overall, no solid association was found between parental occupational exposure to solvents and TGCT risk. The association found with maternal occupational exposure to fuels and petroleum solvents among older men needs further investigation.

OBJECTIVES: This study investigates the associations between the Danish version of a job exposure matrix for COVID-19 (COVID-19-JEM) and Danish register-based SARS-CoV-2 infection information across three waves of the pandemic. The COVID-19-JEM consists of four dimensions on transmission: two on mitigation measures, and two on precarious work characteristics. METHODS: The study comprised 2 021 309 persons from the Danish working population between 26 February 2020 and 15 December 2021. Logistic regression models were applied to assess the associations between the JEM dimensions and overall score and SARS-CoV-2 infection across three infection waves, with peaks in March–April 2020, December–January 2021, and February–March 2022. Sex, age, household income, country of birth, wave, residential region and during wave 3 vaccination status were accounted for. RESULTS: Higher risk scores within the transmission and mitigation dimensions and the overall JEM score resulted in higher odds ratios (OR) of a SARS-CoV-2 infection. OR attenuated across the three waves with ranges of 1.08–5.09 in wave 1, 1.06–1.60 in wave 2, and 1.05–1.45 in those not (fully) vaccinated in wave 3. In wave 3, no associations were found for those fully vaccinated. In all waves, the two precarious work dimensions showed weaker or inversed associations. CONCLUSIONS: The COVID-19-JEM is a promising tool for assessing occupational exposure to SARS-CoV-2 and other airborne infectious agents that mainly spread between people who are in close contact with each other. However, its usefulness depends on applied restrictions and the vaccination status in the population of interest.

OBJECTIVE: This study aimed to investigate whether workplace factors and occupations are associated with SARS-CoV-2 infection or severe COVID-19 in the later waves of the pandemic. METHODS: We studied 552 562 cases with a positive test for SARS-CoV-2 in the Swedish registry of communicable diseases, and 5985 cases with severe COVID-19 based on hospital admissions from October 2020 to December 2021. Four population controls were assigned the index dates of their corresponding cases. We linked job histories to job-exposure matrices to assess the odds for different transmission dimensions and different occupations. We used adjusted conditional logistic analyses to estimate odds ratios (OR) for severe COVID-19 and SARS-CoV-2 with 95% confidence intervals (CI). RESULTS: The highest OR for severe COVID-19 were for: regular contact with infected patients, (OR 1.37, 95% CI 1.23–1.54), close physical proximity (OR 1.47, 95% CI 1.34–1.61), and high exposure to diseases or infections (OR 1.72, 95% CI 1.52–1.96). Mostly working outside had lower OR (OR 0.77, 95% CI 0.57–1.06). The odds for SARS-CoV-2 when mostly working outside were similar (OR 0.83, 95% CI 0.80–0.86). The occupation with the highest OR for severe COVID-19 (compared with low-exposure occupations) was certified specialist physician (OR 2.05, 95% CI 1.31–3.21) among women and bus and tram drivers (OR 2.04, 95% CI 1.49–2.79) among men. CONCLUSIONS: Contact with infected patients, close proximity and crowded workplaces increase the risks for severe COVID-19 and SARS-CoV-2 infection. Outdoor work is associated with decreased odds for SARS-CoV-2 infection and severe COVID-19.

The article presents the discussion on etiology of testicular germ cell tumors (TGCT) suspected to be related to prenatal environmental risk factors. Topics include examining the association between parental occupational exposure to solvents and TGCT risk among their offspring; and impact of the fetal environment is also supported by large geographical variation in incidence and the evolution of TGCT incidence among migrant populations.

The article presents the discussion on investigating the associations between the Danish version of a job exposure matrix for COVID-19 (COVID-19-JEM). Topics include COVID-19 pandemic held the world in its grip, forcing governments to take far-reaching measures such as social distancing, travel restrictions; and higher excess mortality rates were found in sectors of healthcare, food and agriculture, transportation and logistics, manufacturing and facilities.

Objective Previous literature has established associations between psychosocial working conditions and sickness absence (SA), but only few studies have examined associations among younger employees. This study aimed to investigate associations between psychosocial working conditions and SA among employees, aged 15-30 years, who entered the labor market in Denmark between 2010 and 2018. Method We followed 301 185 younger employees in registers for on average 2.6 years. Using job exposure matrices, we assessed job insecurity, quantitative demands, decision authority, job strain, emotional demands, and work-related physical violence. Adjusted rate ratios of SA spells of any length were estimated for women and men separately with Poisson models. Results Among women, employment in occupations with high quantitative demands, low decision authority, high job strain, high emotional demands, or high work-related physical violence was associated with higher rates of SA. Being employed in occupations with high versus low emotional demands showed the strongest association with SA, with a rate ratio of 1.44 [95% confidence interval (CI) 1.41-1.47]. Among men, being employed in occupations with low decision authority showed the strongest association with SA (1.34, 95% CI 1.31-1.37), whereas occupations with high quantitative demands, high job strain, and high emotional demands were associated with lower rates of SA. Conclusion We found that several psychosocial working conditions were associated with SA spells of any length. Associations with SA spells of any length resemble associations with long-term SA, suggesting that results from previous studies on long-term SA may be generalizable to all lengths of SA among younger employees. [ABSTRACT FROM AUTHOR]

Abstract Objective Design Study sample Results Conclusions We aimed to assess the association between occupational noise exposure and tinnitus. Further, to assess whether the association depends on hearing status.In this cross-sectional study, tinnitus (>1 h daily) was regressed on job exposure matrix (JEM)-based or self-reported occupational noise exposure, adjusted for confounders.The 14,945 participants (42% men, 20–59 years) attended a population-based study in Norway (HUNT4, 2017-2019).JEM-based noise exposure, assessed as equivalent continuous sound level normalised to 8-h working days (LEX 8 h), over the working career or as minimum 5 years ≥85 dB) was not associated with tinnitus. Years of exposure ≥80 dB (minimum one) was not associated with tinnitus. Self-reported high noise exposure (>15 h weekly ≥5 years) was associated with tinnitus overall and among persons with elevated hearing thresholds (prevalence ratio (PR) 1.3, 1.0–1.7), however not statistically significantly among persons with normal thresholds (PR 1.1, 0.8–1.5).Our large study showed no association between JEM-based noise exposure and tinnitus. This may to some extent reflect successful use of hearing protection. High self-reported noise exposure was associated with tinnitus, but not among normal hearing persons. This supports that noise-induced tinnitus to a large extent depends on audiometric hearing loss. [ABSTRACT FROM AUTHOR]

The changing nature of contemporary conflicts has resulted in the proliferation of non-international armed conflicts and the active involvement of non-state armed actors. For this reason, it has become essential to combat these groups and encourage them to act in accordance with the law. This study examines the motivations of non-state armed actors who comply with international humanitarian law in order to gain legitimacy and credibility. In this study, the FARC in Colombia and the JEM in Sudan will be examined and it will be tried to determine how they respect the law regarding child soldiers. With the aim of preserving trust in international humanitarian law and increasing respect for human dignity, the study will try to determine the reasons that push non-state armed actors to comply with international humanitarian law as a result of the case analysis. [ABSTRACT FROM AUTHOR]

Objective This study aimed to assess whether workplace exposures as estimated via a COVID-19 job exposure matrix (JEM) are associated with SARS-CoV-2 in the UK. Methods Data on 244 470 participants were available from the Office for National Statistics Coronavirus Infection Survey (CIS) and 16 801 participants from the Virus Watch Cohort, restricted to workers aged 20–64 years. Analysis used logistic regression models with SARS-CoV-2 as the dependent variable for eight individual JEM domains (number of workers, nature of contacts, contact via surfaces, indoor or outdoor location, ability to social distance, use of face covering, job insecurity, and migrant workers) with adjustment for age, sex, ethnicity, index of multiple deprivation (IMD), region, household size, urban versus rural area, and health conditions. Analyses were repeated for three time periods (i) February 2020 (Virus Watch)/April 2020 (CIS) to May 2021), (ii) June 2021 to November 2021, and (iii) December 2021 to January 2022. Results Overall, higher risk classifications for the first six domains tended to be associated with an increased risk of infection, with little evidence of a relationship for domains relating to proportion of workers with job insecurity or migrant workers. By time there was a clear exposure–response relationship for these domains in the first period only. Results were largely consistent across the two UK cohorts. Conclusions An exposure–response relationship exists in the early phase of the COVID-19 pandemic for number of contacts, nature of contacts, contacts via surfaces, indoor or outdoor location, ability to social distance and use of face coverings. These associations appear to have diminished over time. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to explore the relationship between psychosocial job stressors and suicidal behavior (fatal and non-fatal) among Swedish men while controlling for potential confounders. METHODS: Population-based Swedish longitudinal cohort study of male conscripts without previous self-harm (N=1 483 310) enlisting 1968–2002. Conscription examinations included measures of IQ, stress resilience and psychiatric diagnoses. Job demand–control (JDC) exposure was assessed using the Swedish Job Exposure Matrix linked to specific occupations. Suicidal behavior among men aged 30–64 was identified in the National Hospital Register (non-fatal self-harm) and Swedish Cause of Death Register (suicide) during follow-up 2002–2014. Cox regression models were used to estimate associations between JDC category and suicidal behavior. RESULTS: In fully adjusted models, passive jobs (low demand-low control) showed the highest risk of suicidal behavior [hazard ratio (HR) 1.33, 95% confidence interval (CI) 1.25–1.43] compared to those with low strain (low demand-high control), followed by high strain (high demand-low control) (HR 1.12, 95% Cl 1.03–1.22). A lower risk of suicidal behavior was found in the active category, where levels of both demand and control are high (HR 0.64, 95% Cl 0.60–0.70). Separate analyses for suicide as outcome revealed a lower risk of suicide in persons with active jobs (high demands-high control). The passive category showed a higher risk for suicide, but the association did not remain after adjustment for stress resilience and IQ. CONCLUSIONS: These results show that psychosocial job stressors among men are associated with risk for suicidal behavior. Improving job control has the potential to decrease suicidal behavior for this group.

OBJECTIVE: This study aimed to evaluate whether the risk of surgery for subacromial impingement syndrome (SIS) increases with the number of combined occupational mechanical exposures compared with single exposure. METHODS: We reanalyzed data from a register-based cohort study of the entire Danish working population (N=2 374 403) with 14 118 events of surgery for SIS (2003–2008). Exposure information in 10-year windows was obtained by combining occupational codes with a job exposure matrix. For single and combined mechanical exposures, we created three exposure variables of the number of years with specific exposure intensities with or without co-existing mechanical exposures. We used logistic regression as survival analysis. RESULTS: We found exposure–response relations for duration and intensity of each single mechanical exposure except for repetition. The single effect of arm elevation >90º reached a maximum adjusted odds ratio (OR_adj) of 1.7 [95% confidence interval (CI) 1.5–2.0], which increased to 1.8 (95% CI 1.5–2.0), 2.0 (95% CI 1.9–2.2), and 2.2 (95% CI 2.0–2.5) when combined with repetition, force, and both. When combining repetition with arm elevation >90º, force, and both, OR_adj increased from 1.5 (95% CI 1.3–1.8) to 2.1 (95% CI 1.8–2.4), 2.5 (95% CI 2.4–2.9), and 2.7 (95% CI 2.4–3.0). For force, OR_adj increased from 2.5 (95% CI 2.1–2.9) to 2.6 (95% CI 2.3–2.8), 2.8 (95% CI 2.4–3.2), and 3.0 (95% CI 2.6–3.4). CONCLUSION: We found an increased risk of surgery for SIS with the number of combined exposures; the risk was especially pronounced when the combined exposures included force.

OBJECTIVE: This study investigated time trends in occupational exposure to various chemicals in Sweden and the distribution across demographic and labor market sectors. METHODS: Exposure to six chemicals was investigated from 1980 to 2013 by application of a job exposure matrix to national population registers. Respirable crystalline silica (RCS), diesel engine exhaust, welding fumes, wood dust, chlorinated hydrocarbon solvents, and lead were selected to represent different groups of chemicals. Trends in exposure prevalence were investigated by linear regression and compared to the occupationally active population. Confidence intervals for the rate of change over time were obtained by bootstrapping. RESULTS: The proportion of workers born outside the Nordic countries increased over time in those exposed to RCS, diesel exhaust and wood dust. There was a shift of exposed jobs to small companies (

Objective This study investigated time trends in occupational exposure to various chemicals in Sweden and the distribution across demographic and labor market sectors. Methods Exposure to six chemicals was investigated from 1980 to 2013 by application of a job exposure matrix to national population registers. Respirable crystalline silica (RCS), diesel engine exhaust, welding fumes, wood dust, chlorinated hydrocarbon solvents, and lead were selected to represent different groups of chemicals. Trends in exposure prevalence were investigated by linear regression and compared to the occupationally active population. Confidence intervals for the rate of change over time were obtained by bootstrapping. Results The proportion of workers born outside the Nordic countries increased over time in those exposed to RCS, diesel exhaust and wood dust. There was a shift of exposed jobs to small companies (<50 employees), especially for RCS, welding fumes, wood dust, and chlorinated hydrocarbon solvents. For RCS and welding fumes, there was a marked drop in exposure levels from 1980 to 1990 but small changes thereafter. Exposure to lead diminished, both in terms of prevalence and intensity. Conclusions Over time, several exposures tended to shift to small companies, the construction sector, and migrant workers, all factors being indicative of less well-controlled working conditions. Occupational exposure to chlorinated organic solvents and lead diminished, while exposure levels to RCS and welding fumes have changed little since 1990. In view of the serious and well-established negative health effects, increased efforts to reduce exposure to RCS and welding fumes are needed. [ABSTRACT FROM AUTHOR]

Objective This study aimed to evaluate whether the risk of surgery for subacromial impingement syndrome (SIS) increases with the number of combined occupational mechanical exposures compared with single exposure. Methods We reanalyzed data from a register-based cohort study of the entire Danish working population (N=2 374 403) with 14 118 events of surgery for SIS (2003–2008). Exposure information in 10-year windows was obtained by combining occupational codes with a job exposure matrix. For single and combined mechanical exposures, we created three exposure variables of the number of years with specific exposure intensities with or without co-existing mechanical exposures. We used logistic regression as survival analysis. Results We found exposure–response relations for duration and intensity of each single mechanical exposure except for repetition. The single effect of arm elevation >90º reached a maximum adjusted odds ratio (ORadj) of 1.7 [95% confidence interval (CI) 1.5–2.0], which increased to 1.8 (95% CI 1.5–2.0), 2.0 (95% CI 1.9–2.2), and 2.2 (95% CI 2.0–2.5) when combined with repetition, force, and both. When combining repetition with arm elevation >90º, force, and both, ORadj increased from 1.5 (95% CI 1.3–1.8) to 2.1 (95% CI 1.8–2.4), 2.5 (95% CI 2.4–2.9), and 2.7 (95% CI 2.4–3.0). For force, ORadj increased from 2.5 (95% CI 2.1–2.9) to 2.6 (95% CI 2.3–2.8), 2.8 (95% CI 2.4–3.2), and 3.0 (95% CI 2.6–3.4).Conclusion We found an increased risk of surgery for SIS with the number of combined exposures; the risk was especially pronounced when the combined exposures included force. [ABSTRACT FROM AUTHOR]

Objective This study aimed to explore the relationship between psychosocial job stressors and suicidal behavior (fatal and non-fatal) among Swedish men while controlling for potential confounders. Methods Population-based Swedish longitudinal cohort study of male conscripts without previous self-harm (N=1 483 310) enlisting 1968–2002. Conscription examinations included measures of IQ, stress resilience and psychiatric diagnoses. Job demand–control (JDC) exposure was assessed using the Swedish Job Exposure Matrix linked to specific occupations. Suicidal behavior among men aged 30–64 was identified in the National Hospital Register (non-fatal self-harm) and Swedish Cause of Death Register (suicide) during follow-up 2002–2014. Cox regression models were used to estimate associations between JDC category and suicidal behavior. Results In fully adjusted models, passive jobs (low demand-low control) showed the highest risk of suicidal behavior [hazard ratio (HR) 1.33, 95% confidence interval (CI) 1.25–1.43] compared to those with low strain (low demand-high control), followed by high strain (high demand-low control) (HR 1.12, 95% Cl 1.03–1.22). A lower risk of suicidal behavior was found in the active category, where levels of both demand and control are high (HR 0.64, 95% Cl 0.60–0.70). Separate analyses for suicide as outcome revealed a lower risk of suicide in persons with active jobs (high demands-high control). The passive category showed a higher risk for suicide, but the association did not remain after adjustment for stress resilience and IQ. Conclusions These results show that psychosocial job stressors among men are associated with risk for suicidal behavior. Improving job control has the potential to decrease suicidal behavior for this group. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to construct a job exposure matrix (JEM) for risk of becoming infected with the SARS-CoV-2 virus in an occupational setting. METHODS: Experts in occupational epidemiology from three European countries (Denmark, The Netherlands and the United Kingdom) defined the relevant exposure and workplace characteristics with regard to possible exposure to the SARS-CoV-2 virus. In an iterative process, experts rated the different dimensions of the COVID-19-JEM for each job title within the International Standard Classification of Occupations system 2008 (ISCO-08). Agreement scores, weighted kappas, and variances were estimated. RESULTS: The COVID-19-JEM contains four determinants of transmission risk [number of people, nature of contacts, contaminated workspaces and location (indoors or outdoors)], two mitigation measures (social distancing and face covering), and two factors for precarious work (income insecurity and proportion of migrants). Agreement scores ranged from 0.27 [95% confidence interval (CI) 0.25–0.29] for ‘migrants’ to 0.76 (95% CI 0.74–0.78) for ‘nature of contacts’. Weighted kappas indicated moderate-to-good agreement for all dimensions [ranging from 0.60 (95% CI 0.60–0.60) for ‘face covering’ to 0.80 (95% CI 0.80–0.80) for ‘contaminated workspaces’], except for ‘migrants’ (0.14 (95% CI -0.07–0.36). As country differences remained after several consensus exercises, the COVID-19-JEM also has a country-axis. CONCLUSIONS: The COVID-19-JEM assesses the risk at population level using eight dimensions related to SARS-COV-2 infections at work and will improve our ability to investigate work-related risk factors in epidemiological studies. The dimensions of the COVID-19-JEM could also be valuable for other future communicable diseases in the workplace.

Driving fatigue refers to a phenomenon in which a driver's physiological and psychological functions become unbalanced after a long period of continuous driving, and their driving skills decline objectively. The hidden dangers of driving fatigue to traffic safety should not be underestimated. In this work, we propose a judgment excitation mode (JEM), which adds secondary cognitive tasks to driving behavior through dual-channel human–computer interaction, so as to delay the occurrence of driving fatigue. We used multifractal detrended fluctuation analysis (MF-DFA) to study the dynamic properties of subjects' EEG, and analyzed the effect of JEM on fatigue retardation by Hurst exponent value and multifractal spectrum width value. The results show that the multifractal properties of the two driving modes (normal driving mode and JEM) are significantly different. The JEM we propose can effectively delay the occurrence of driving fatigue, and has good prospects for future practical applications. [ABSTRACT FROM AUTHOR]

Objectives To compare the exposure data generated by using the Canadian job-exposure matrix (CANJEM) with data generated by expert assessment, for jobs held by women. Methods We selected 69 occupational agents that had been assessed by experts for each of 3403 jobs held by 998 women in a population-based case–control study of lung cancer. We then assessed the same agents among the same jobs by linking their occupation codes to CANJEM and thereby derived probability of exposure to each of the agents in each job. To create binary exposure variables, we dichotomized probability of exposure using two cutpoints: 25 and 50% (referred to as CANJEM-25% and CANJEM-50%). Using jobs as units of observation, we estimated the prevalence of exposure to each selected agent using CANJEM-25% and CANJEM-50%, and using expert assessment. Further, using expert assessment as the gold standard, for each agent, we estimated CANJEM's sensitivity, specificity, and kappa. Results CANJEM-based prevalence estimates correlated well with the prevalences assessed by the experts. When comparing CANJEM-based exposure estimates with expert-based exposure estimates, sensitivity, specificity, and kappa varied greatly among agents, and between CANJEM-25% and CANJEM-50% probability of exposure. With CANJEM-25%, the median sensitivity, specificity, and kappa values were 0.49, 0.99, and 0.46, respectively. Analogously, with CANJEM-50%, the corresponding values were 0.26, 1.00, and 0.35, respectively. For the following agents, we observed high concordance between CANJEM- and expert-based assessments (sensitivity ≥0.70 and specificity ≥0.99): fabric dust, cotton dust, synthetic fibres, cooking fumes, soldering fumes, calcium carbonate, and tin compounds. We present concordance estimates for each of 69 agents. Conclusions Concordance between CANJEM and expert assessment varied greatly by agents. Our results indicate which agents provide data that mimic best those obtained with expert assessment. [ABSTRACT FROM AUTHOR]

BackgroundThe goal of this study is to develop a general population job-exposure matrix (GPJEM) on asbestos to estimate occupational asbestos exposure levels in the Republic of Korea.MethodsThree Korean domestic quantitative exposure datasets collected from 1984 to 2008 were used to build the GPJEM. Exposure groups in collected data were reclassified based on the current Korean Standard Industrial Classification (9th edition) and the Korean Standard Classification of Occupations code (6th edition) that is in accordance to international standards. All of the exposure levels were expressed by weighted arithmetic mean (WAM) and minimum and maximum concentrations.ResultsBased on the established GPJEM, the 112 exposure groups could be reclassified into 86 industries and 74 occupations. In the 1980s, the highest exposure levels were estimated in "knitting and weaving machine operators" with a WAM concentration of 7.48 fibers/mL (f/mL); in the 1990s, "plastic products production machine operators" with 5.12 f/mL, and in the 2000s "detergents production machine operators" handling talc containing asbestos with 2.45 f/mL. Of the 112 exposure groups, 44 groups had higher WAM concentrations than the Korean occupational exposure limit of 0.1 f/mL.ConclusionThe newly constructed GPJEM which is generated from actual domestic quantitative exposure data could be useful in evaluating historical exposure levels to asbestos and could contribute to improved prediction of asbestos-related diseases among Koreans.

OBJECTIVE: The aim of this study was to explore the association between occupational exposure to diesel exhaust and polycyclic aromatic hydrocarbons (PAH), respectively, and breast cancer subtypes. METHODS: The study included 38 375 women

OBJECTIVES: Exposure to environmental noise has been associated with an increased risk of cardiovascular diseases and diabetes, but evidence for occupational noise is limited and conflicting, especially related to pregnancy outcomes. This study aimed to evaluate the association of occupational noise exposure with hypertensive disorders of pregnancy (HDP) and gestational diabetes. METHODS: Our population-based cohort study utilized data on 1 109 516 singletons born to working mothers in Sweden between 1994–2014 from the Medical Birth Register and the Longitudinal Integration Database for Health Insurance and Labor Market Studies. Noise exposure came from a job exposure matrix (JEM) in five categories 85 dB(A). Relative risks (RR), adjusted for confounders and other job exposures, were calculated by modified Poisson regressions for the full sample and a subsample of first-time mothers reporting full-time work. RESULTS: Exposure to 80–85 dB(A) of noise was associated with an increased risk of all HDP [RR 1.12, 95% confidence interval (CI) 1.05–1.18] and preeclampsia alone (RR 1.14, 95% CI 1.07–1.22) in the full sample. Results were similar for first-pregnancy, full-time workers. Exposure to >85 dB(A) of noise was also associated with an increased risk of gestational diabetes (RR 1.57, 95% CI 1.10–2.24) in the analysis restricted to first-time mothers working full-time. CONCLUSION: In this study, exposure to noise was associated with an increased risk for HDP and gestational diabetes, particularly in first-time mothers who work full-time. Further research is needed to confirm findings and identify the role of hearing protection on this association so prevention policies can be implemented.

OBJECTIVES: The study aims to explore the prospective associations of the psychosocial work exposures of the job strain model with cardiovascular mortality, including mortality for ischemic heart diseases (IHD) and stroke, using various time-varying exposure measures in the French working population of employees. METHODS: The study was based on a cohort of 798 547 men and 697 785 women for which job history data from 1976 to 2002 were linked to mortality data and causes of death from the national death registry. Psychosocial work exposures from the validated job strain model questionnaire were assessed using a job-exposure matrix (JEM). Three time-varying measures of exposure were studied: current, cumulative, and recency-weighted cumulative exposure. Cox proportional hazards models were used to examine the associations between psychosocial work exposures and cardiovascular mortality. RESULTS: Within the 1976–2002 period, there were 19 264 cardiovascular deaths among men and 6181 among women. Low decision latitude, low social support, job strain, iso-strain, passive job, and high strain were associated with cardiovascular mortality. Most of these associations were also observed for IHD and stroke mortality. The comparison between the different exposure measures suggested that current exposure may be more important than cumulative (or past) exposure. The population fractions of cardiovascular mortality attributable to job strain were 5.64% for men and 6.44% for women. CONCLUSIONS: Psychosocial work exposures of the job strain model may play a role in cardiovascular mortality. The estimated burden of cardiovascular mortality associated with these exposures underlines the need for preventive policies oriented toward the psychosocial work environment.

OBJECTIVES: This study aimed to examine the association between job strain and incident coronary heart disease (CHD) in Denmark, while accounting for changes of job strain. METHODS: We included all employees residing in Denmark in 2000, aged 30–59 years with no prevalent CHD (N=1 660 150). We determined exposure to job strain from 1996–2009 using a job exposure matrix (JEM) with annual updates. Follow-up for incident CHD was from 2001–2010 via linkage to health records. We used Cox regression to calculate hazard ratios (HR) and 95% confidence intervals (CI) for the association between job strain and incident CHD. RESULTS: During 16.1 million person-years, we identified 24 159 incident CHD cases (15.0 per 10 000 person-years). After adjustment for covariates, job strain in 2000 predicted onset of CHD during a mean follow-up of 9.71 years (HR 1.10, 95% CI 1.07–1.13). When analyzing changes in job strain from one year to the next and CHD in the subsequent year, persistent job strain (HR 1.07, 95% CI 1.03–1.10), onset of job strain (HR 1.20, 95% CI 1.12–1.29) and removal of strain (HR 1.20, 95% CI 1.12–1.28) were associated with higher CHD incidence compared to persistent no job strain. Associations were similar among men and women. CONCLUSIONS: Job strain is associated with a higher risk of incident CHD in Denmark. As we used a JEM, we can rule out reporting bias. However, under- or overestimation of associations is possible due to non-differential misclassification of job strain and residual confounding by socioeconomic position.

OBJECTIVE: Albeit a pivotal risk for the development of hand eczema (HE), the exposure–response relationship between wet work and HE remains to be further investigated. Knowledge on exposure–response is important regarding preventive measures, medico-legal regulations and job-counseling. Recently, a job-exposure matrix (JEM) for wet work was developed, providing information on the likelihood of wet work. By combining the JEM with data on HE we aimed to investigate the relationship between extent of wet work and HE. METHODS: This study is a case–referent study including patients registered in the National Database of Contact Allergy, Denmark, and comprises data on sex, age, atopic dermatitis, HE, face eczema and patch testing results. Patients with HE served as cases and patients with facial eczema served as referents. Information on profession was retrieved from the DOC*X database in accordance with the DISCO-88 classification system. A wet-work-specific JEM provides – for each profession – an estimate for (i) the likelihood of wet work lasting ≥2 hours/day and (ii) the average number of hours of wet work per day. RESULTS: After two hours of wet hands and glove wear, the odds ratio (OR) was 3.49 and 3.19, respectively, for females and 2.41 and 1.82, respectively, for males. Females had a higher risk of HE than males with probability of wet hands

Job-exposure matrices (JEM) are a common method for exposure assessment in occupational epidemiology. The first JEM were described in the early 1980s (1, 2) and have been used in a wide range of settings ever since. A recent review on methods for retrospective exposure assessment in the general population revealed that more than a quarter of the studies on cancer applied a JEM (3). Where JEM originally assigned exposures at a qualitative or semi-quantitative level based on expert ratings, quantitative exposure estimates can also be derived when measurements are used to calibrate these ratings (4-6). A JEM typically consists of job and exposure axes. The major advantage of JEM is that job histories can be translated into specific exposures in a systematic and unbiased way. It is basically a computerized linkage of exposure estimates to job codes, and, as such, JEM represent a highly efficient and reproducible methodology. This way, a standardized exposure assessment within and between studies can be guaranteed, and any misclassification is expected to be non-differential with respect to the health outcome. Once developed, a JEM is relatively easy to apply and less costly than case-by-case expert assessment. These benefits make JEM a particularly useful instrument for exposure assessment in large-scale, general population studies. Such studies (eg, based on register data) permit collection of full occupational histories and enable the study of rare diseases or subtypes. Subjects have typically worked in a wide variety of occupations and industries. Detailed exposure information, which can more easily be collected in industry-based cohorts, is often not available. For register-based cohorts, collected occupational histories are also typically limited to the basic information of job titles and industries. Using JEM, exposures can be assessed for many agents and stressors, based solely on job titles. The DOC*X project is a good example of the use of register data in occupational epidemiology (7). The large number of subjects – the full working population of Denmark for several decades – offers unique opportunities for studying new associations between a variety of exposures and various health outcomes. Individual data from several databases, including health and labour registries, were linked by a personal identifier. For each cohort member, job title and industry have been annually registered and coded (7). Subsequently, the project has been linking a series of JEM to this nationwide cohort to assess several kinds of occupational exposures. A couple of these efforts have been published in this issue of the Scandinavian Journal of Work, Environment and Health to assess the association between physical activities at work and acute myocardial infarction (8) and the risk of work-related hand eczema in relation to wet work (9). It is impossible to go back to all individuals in this cohort to collect detailed information on their occupations: firstly because part of the cohort has died over the years but also due to practical reasons given the large numbers. So, by applying JEM, the Danes make the best use of the information available in their registry data. The ease of using a JEM, by simply assigning exposures based on job titles, also has a flipside. By design, a JEM allocates the same exposure estimates to all workers with the same job title. This aspect represents the main drawback since it is well-recognized that there can be substantial inter-individual variability (10). In other words, a JEM completely dismisses exposure heterogeneity between workers in similar jobs, as has also been acknowledged by the authors of the DOC*X studies (8, 9). Heterogeneity between workers may be larger for some types of exposures than others, particularly when exposures are largely determined by specific tasks. To illustrate, when assessing welding fumes, job title alone does not provide information on different tasks and circumstances that influence the level and frequency of exposure to welding fumes (11). For exposures related to tasks like welding, decreasing or pesticide application – but also exposures such as shift work or certain psychosocial working conditions – exposure assessment based on job title alone may not be sufficient. Thus, researchers need to critically evaluate for each given exposure, if that exposure can be reasonably assessed on the job group level or if further assessment on the workplace, work unit or individual-worker level is needed. A large part of heterogeneity is determined by the workers’ behavior (12). Although this is virtually impossible to take into account in a JEM, some of the exposure heterogeneity may be accounted for by adding more detail, ie, by expanding the number of axes of the JEM. For example, an industry-axis, a time dimension, or region-, sex- and age-specific estimates may help explain part of the exposure heterogeneity. Importantly, this type of information is also typically available in the large studies where the JEM are being applied to. The JEM for wet work used by Lund et al (9) provided sex-specific estimates. A similar effort has been described for mechanical and psychosocial work exposures in Norway (13). In addition to within-job (ie, between-worker) variability, exposures may have large temporal (ie, within-worker) variability. Levels can vary from day-to-day or over the course of the work day, the variability of which is not captured in a JEM. When studying acute health effects, for example, short-term high exposures may be more relevant than the annual average or cumulative levels and a JEM may not provide the appropriate assessment. Many different JEM, in all forms and shapes, have been developed over the last 40 years. Due to the lack of a gold standard, JEM cannot be truly validated. Several studies, however, have described the performance of JEM (14–16). For asbestos, for instance, poor agreement between different JEM has been reported, indicating variable performance (14). Exposure assessment methods can also be evaluated using known associations with health outcomes. Using lung cancer case–control data, comparisons with other methods showed that a JEM for asbestos could outperform self-reported exposure (16) and perform as well as case-by-case expert assessment in a multicenter study (15). Yet, as indicated above, the performance of a JEM will depend on the exposure and effect of interest. Improvement in the use of JEM could be achieved by harmonizing existing JEM. A harmonized JEM, which provides a standardized exposure assessment across regions and time periods, would be highly valuable for pooled analyses. Such large-scale analyses will offer unique opportunities to study exposure–disease associations that have been understudied until now due to lack of statistical power. JEM will be invaluable instruments to such (exploratory) exercises. Derivation of exposure–response relations requires quantification of exposure. Development of more quantitative JEM, as first described for the multinational SYNERGY project on lung cancer (4) and the Shanghai Women’s Health Study (6), may further increase the impact of occupational studies. However, a quantitative JEM will still have the same limitation of assuming homogeneity within jobs and large amounts of (measurement) data are needed to develop a quantitative JEM. Data mining techniques could be explored to make better use. The coding of job titles is another major challenge related to the use of JEM. Manual coding of each individual’s job history in large epidemiological studies is a very time-consuming task. As a result, many of these studies are not used to their full potential for occupational health outcomes. Further improvement could therefore be achieved by systems that automatically translate free text into occupational codes, increasing the efficiency and feasibility of investigating occupational risk factors (using JEM) in large-scale epidemiological studies. Efforts in developing automatic coding in the US have shown agreements with manual coding of around 50% (17, 18). Automated coding systems would not be applicable to most registry data, however, since job information is only available as a code. For pooling these registry data with other data, or for application of another JEM, crosswalks between systems can be the solution. In addition to differences between human coders, crosswalks may also introduce disagreement between codes and actual jobs, possibly leading to further misclassification of exposure. Interestingly, within DOC*X it was shown that errors in job coding had limited effect on the exposure assessment of wood dust, lifting, standing/walking, arm elevation, and noise (19). Previous studies also reported that the effects of disagreements in job coding generally diminish in the exposure assessment stage (12, 20). Specificity is crucial when the prevalence of occupational exposure is low, which is often the case in the general population because possible associations may otherwise be severely underestimated. When exposures are more prevalent, sensitivity becomes more important (12). Since the performance of a JEM is also determined by the between-worker (ie, within job) and between-job variance, the level of detail of the job classification plays an important role. Occupational classification systems have primarily been developed from a social-economic perspective. These systems, either international or national coding schemes, are therefore not necessarily reflecting exposure categories in the best way. Developing new or adjusted coding systems for exposure assessment may help moving the occupational health field forward. Several research initiatives are currently working on such improvements in the use of JEM, including the Network on the Coordination and Harmonisation of European Occupational Cohorts (OMEGA-NET, omeganetcohorts.eu) and the Exposome Project for Health and Occupational Research (EPHOR, www.ephor-project.eu). In conclusion, a JEM can be a very handy tool for exposure assessment in occupational epidemiology, particularly in large-scale studies with limited occupational information. When selecting the most suitable exposure assessment method, however, researchers should always remain critical. Know when a JEM has added value and recognize its limitations. References 1. Hoar SK, Morrison AS, Cole P, Silverman DT. An occupation and exposure linkage system for the study of occupational carcinogenesis. J Occup Med. 1980;22(11):722-6. 2. Pannett B, Coggon D, Acheson ED. A job-exposure matrix for use in population based studies in England and Wales. Br J Ind Med. 1985;42(11):777-83. https://doi.org/10.1136/oem.42.11.777 3. Ge CB, Friesen MC, Kromhout H, Peters S, Rothman N, Lan Q, et al. Use and Reliability of Exposure Assessment Methods in Occupational Case-Control Studies in the General Population: Past, Present, and Future. Ann Work Expo Health. 2018;62(9):1047-63. https://doi.org/10.1093/annweh/wxy080 4. Peters S, Vermeulen R, Portengen L, Olsson A, Kendzia B, Vincent R, et al. Modelling of occupational respirable crystalline silica exposure for quantitative exposure assessment in community-based case-control studies. J Environ Monit. 2011;13(11):3262-8. https://doi.org/10.1039/c1em10628g 5. Peters S, Vermeulen R, Portengen L, Olsson A, Kendzia B, Vincent R, et al. SYN-JEM: A Quantitative Job-Exposure Matrix for Five Lung Carcinogens. Ann Occup Hyg. 2016;60(7):795-811. https://doi.org/10.1093/annhyg/mew034 6. Friesen MC, Coble JB, Lu W, Shu XO, Ji BT, Xue S, et al. Combining a job-exposure matrix with exposure measurements to assess occupational exposure to benzene in a population cohort in shanghai, china. Ann Occup Hyg. 2012;56(1):80-91. https://doi.org/10.1136/oemed-2011-100382.81 7. Flachs EM, Petersen SEB, Kolstad HA, Schlunssen V, Svendsen SW, Hansen J, et al. Cohort Profile: DOC*X: a nationwide Danish occupational cohort with eXposure data - an open research resource. Int J Epidemiol. 2019;48(5):1413-k. https://doi.org/10.1093/ije/dyz110 8. Bonde JPE, Flachs EM, Madsen IE, Petersen SB, Andersen JH, Hansen J, et al. Acute myocardial infarction in relation to physical activities at work: a nationwide follow-up study based on job-exposure matrices. Scand J Work Environ Health. 2019. https://doi.org/10.5271/sjweh.3863 9. Lund T, Petersen SB, Flachs EM, Ebbehoj NE, Bonde JP, Agner T. Risk of work-related hand eczema in relation to wet work exposure. Scand J Work Environ Health. 2020. https://doi.org/10.5271/sjweh.3876 10. Kromhout H, Symanski E, Rappaport SM. A comprehensive evaluation of within- and between-worker components of occupational exposure to chemical agents. Ann Occup Hyg. 1993;37(3):253-70. 11. IARC Working Group. Volume 118: Welding, Indium Tin Oxide, Molybdenum Trioxide.: IARC Monogr Eval Carcinog Risks Hum; 2018. 12. Kromhout H, Vermeulen R. Application of job-exposure matrices in studies of the general population. Some clues to their performance. European Respiratory Review. 2001;11:80-90. 13. Hanvold TN, Sterud T, Kristensen P, Mehlum IS. Mechanical and psychosocial work exposures: the construction and evaluation of a gender-specific job exposure matrix (JEM). Scand J Work Environ Health. 2019;45(3):239-47. https://doi.org/10.5271/sjweh.3774 14. Offermans NS, Vermeulen R, Burdorf A, Peters S, Goldbohm RA, Koeman T, et al. Comparison of expert and job-exposure matrix-based retrospective exposure assessment of occupational carcinogens in The Netherlands Cohort Study. Occup Environ Med. 2012;69(10):745-51. https://doi.org/10.1136/oemed-2011-100556 15. Peters S, Vermeulen R, Cassidy A, Mannetje A, van Tongeren M, Boffetta P, et al. Comparison of exposure assessment methods for occupational carcinogens in a multi-centre lung cancer case-control study. Occup Environ Med. 2011;68(2):148-53. https://doi.org/10.1136/oem.2010.055608 16. Hardt JS, Vermeulen R, Peters S, Kromhout H, McLaughlin JR, Demers PA. A comparison of exposure assessment approaches: lung cancer and occupational asbestos exposure in a population-based case-control study. Occup Environ Med. 2014;71(4):282-8. https://doi.org/10.1136/oemed-2013-101735 17. Russ DE, Ho KY, Colt JS, Armenti KR, Baris D, Chow WH, et al. Computer-based coding of free-text job descriptions to efficiently identify occupations in epidemiological studies. Occup Environ Med. 2016;73(6):417-24. https://doi.org/10.1136/oemed-2015-103152 18. Burstyn I, Slutsky A, Lee DG, Singer AB, An Y, Michael YL. Beyond crosswalks: reliability of exposure assessment following automated coding of free-text job descriptions for occupational epidemiology. Ann Occup Hyg. 2014;58(4):482-92. 19. Petersen SB, Flachs EM, Svendsen SW, Marott JL, Budtz-Jorgensen E, Hansen J, et al. Influence of errors in job codes on job exposure matrix-based exposure assessment in the register-based occupational cohort DOC*X. Scand J Work Environ Health. 2019. https://doi.org/10.5271/sjweh.3857 20. Koeman T, Offermans NS, Christopher-de Vries Y, Slottje P, Van Den Brandt PA, Goldbohm RA, et al. JEMs and incompatible occupational coding systems: effect of manual and automatic recoding of job codes on exposure assignment. Ann Occup Hyg. 2013;57(1):107-14.

OBJECTIVES: A job exposure matrix (JEM) is a tool to estimate workers’ exposure to occupational physical risk factors. We evaluated the performance of two general population JEM (CONSTANCES and O*NET) to detect known exposure–disease relationships in an American prospective cohort study. We compared exposure estimates from three data sources and explored whether combining exposures from these two JEM, or combining exposure from each JEM with individual-level measures, improved prediction of carpal tunnel syndrome (CTS). METHODS: Using Cox proportional hazard models, we evaluated relationships between physical work exposure and incident CTS of 2393 workers using JEM-assigned and individual-level measure exposure information. We compared exposure estimates using Spearman’s rank correlation and Cohen’s kappa. We compared combined exposure models to single source exposure models by using binomial logistic regression and examined differences based on model fit and performance. RESULTS: The O*NET JEM [hazard ratio (HR) range 1.3–2.01] demonstrated generally similar exposure–disease associations as individual-level measures (HR range 1.00–1.42); we found fewer associations with the CONSTANCES JEM (HR range 1.08–2.05). Comparisons between the three sources showed stronger correlations and agreement at the job versus worker level. Combined models improved goodness-of-fit and had lower Akaike information criterion (AIC) values compared to single-source models. CONCLUSIONS: JEM can be applied cross nationally and there is potential to combine complementary exposure methods to improve estimation of workplace physical exposures in the prediction of CTS. More investigations are needed to explore exposure-disease associations in other samples and combinations of exposure data from different methods.

Objective This study aimed to evaluate sex-specific risks of acute myocardial infarction (AMI) according to lifting and standing/walking at work. METHODS: The study population included 1.15 million Danish wage earners. Annual job codes from 1976 onwards were linked to specific exposures using job-exposure matrices (JEM). Cases of AMI during follow-up 1996–2016 were retrieved from national registers. Incidence rate ratios (IRR) were computed by Poisson regression adjusting for demographic and JEM-assessed lifestyle factors. Models addressed physical activities at work the previous 0–2 years (short-term risk) and cumulative physical activities (long-term risk). RESULTS: During 21.4 million person-years of follow-up, 22 037 AMI occurred in men and 6942 in women. Exposure–response relationships between recent physical activities at work and AMI were not evident. In men, the fully adjusted long-term IRR for the highest of five exposure categories compared to the lowest were 1.09 [95% confidence interval (CI) 1.03–1.15] for lifting and 1.01 (95% CI 0.96–1.07) for standing/walking. In women, the corresponding figures were 1.27 (95% CI 1.15–1.40) and 1.18 (95% CI 1.07–1.30). The latter risk estimate was strongly attenuated, and the trend became insignificant when adjusted for lifting. Findings were only partially supported by sensitivity analyses. CONCLUSION: The study provides limited support to the hypothesis that long-term lifting and standing/walking at work is related to increased risk of AMI. Possible effects of acute physical exertion are not addressed and bias towards the null because of crude exposure assignment cannot be ruled out.

OBJECTIVE: Job-exposure matrices (JEM) may be efficient for exposure assessment in occupational epidemiological studies, but they rely on valid job information. We evaluated the agreement between JEM-based exposure estimates according to self-reported job titles converted to DISCO-88 codes and according to register-based DISCO-88 codes in the Danish Occupational Cohort with eXposure data (DOC*X). Furthermore, we evaluated the agreement between these two sets of DISCO-88 codes. METHODS: We used JEM regarding wood dust, lifting, standing/walking, arm elevation >90°, and noise from DOC*X. Participants from previous questionnaire studies were assigned JEM-based exposure estimates using (i) self-reported job titles converted to DISCO-88 codes and (ii) DISCO-88 codes registered in DOC*X, in four time periods (1976–78: N=7707; 1981–83: N=2193; 1991–94: N=2664; 2004: N=11 782). Agreement between the exposure estimates and between the DISCO-88 codes (four-digit levels, 1–4) was evaluated by kappa (κ) statistics. Sensitivities were calculated using the self-reported observation as the gold standard. RESULTS: We found substantial agreement (κ>0.60) between exposure estimates for all types of job-exposures and all time periods except for one κ. Low sensitivity (30–65%) was found for the period 1981–83, but for the other time periods the sensitivities varied between 60–91%. For individual 4-digit DISCO-88 codes, the sensitivities varied substantially and overall the sensitivities increased by lower digit level of DISCO-88. CONCLUSION: The validity of the DISCO-88 codes in DOC*X was generally high. Substantial agreement was found for the JEM-based exposure estimates and the DISCO-88 codes per se, although the DISCO-88 code-specific agreement varied across digit levels and time periods.

OBJECTIVES: The aim of this study was to investigate if exposure to chemicals in the workplace was associated with an increased risk of postmenopausal breast cancer. METHODS: The study comprised women born 1923–1950 living in Malmö city, Sweden, 1991–1996, and enrolled for a prospective population cohort study. Occupational exposure to various chemicals was assessed from job-exposure matrices. An extensive set of individual data on hormonal breast cancer risk factors were collected via a baseline questionnaire and used for confounding control. First time diagnoses of invasive breast cancer were identified through the Swedish Cancer Registry until end of follow-up on 31 December 2013. RESULTS: Of 16 084 women, 1011 were diagnosed with breast cancer. Women exposed to chemicals in their occupational environment had a statistically significant increased risk [adjusted hazard ratio (HR_adj) 1.26, 95% confidence interval (CI) 1.02–1.54] of breast cancer, and the risk correlated with duration of exposure. Investigation of risk in association with specific chemicals showed a non-significantly elevated risk after exposure to organic solvents. More than ten years of exposure to diesel exhaust was associated with an increased risk (HR_adj 1.69, 95% CI 1.01–2.82). Occupational chemical exposures account for 2% of the breast cancer cases in this population. CONCLUSIONS: Occupational exposure to chemicals in general was associated with an elevated risk of breast cancer. A slight elevation of risk was seen after exposure to organic solvents. A statistically significant elevation of risk after >10 years of exposure to diesel exhaust was an unexpected finding.

Driving fatigue refers to a phenomenon in which a driver’s physiological and psychological functions become unbalanced after a long period of continuous driving, and their driving skills decline objectively. The hidden dangers of driving fatigue to traffic safety should not be underestimated. In this work, we propose a judgment excitation mode (JEM), which adds secondary cognitive tasks to driving behavior through dual-channel human–computer interaction, so as to delay the occurrence of driving fatigue. We used multifractal detrended fluctuation analysis (MF-DFA) to study the dynamic properties of subjects’ EEG, and analyzed the effect of JEM on fatigue retardation by Hurst exponent value and multifractal spectrum width value. The results show that the multifractal properties of the two driving modes (normal driving mode and JEM) are significantly different. The JEM we propose can effectively delay the occurrence of driving fatigue, and has good prospects for future practical applications.

OBJECTIVES: The aim of this study was to (i) construct and evaluate a gender-specific job exposure matrix (JEM) for mechanical and psychosocial work exposures and (ii) test its predictive validity for low-back pain. METHODS: We utilized data from the Norwegian nationwide Survey of Living Conditions on work environment in 2006 and 2009. We classified occupations on a 4-digit level based on the Norwegian version of the International Standard Classification of Occupations (ISCO-88). The mechanical and psychosocial exposure information was collected by personal telephone interviews and included exposures that were known risk factors for low-back pain. We evaluated the agreement between the individual- and JEM-based exposure estimates, with kappa, sensitivity and specificity measures. We assessed the JEM`s predictive validity by testing the associations between low-back pain and the individual- and JEM-based exposure. RESULTS: The results showed an overall fair-to-moderate agreement between the constructed JEM and individual work exposures. The JEM performed considerably better for mechanical work exposures compared with psychosocial work exposures. The predictive validity of the mechanical and psychosocial JEM showed a consistently lower but predominantly reproducible association with low-back pain for both genders. CONCLUSIONS: The mechanical estimates and psychosocial stressors, such as psychological demands, monotonous work and decision latitude in the constructed JEM, may be useful in large epidemiological register studies. The predictive validity of the matrix was evaluated as being overall acceptable, it can thus be an effective and versatile approach to estimate the relationship between work exposures and low-back pain.

OBJECTIVES: The aim of this study was to determine the association between occupational biomechanical exposures and occurrence of surgically treated ulnar nerve entrapment (UNE). METHODS: A cohort of 229 689 male construction workers who participated in a national occupational health surveillance program (1971–1993) were examined prospectively over a 13-year case ascertainment period (2001–2013) for surgically treated UNE. Job title (construction trade), smoking status, height, weight and age were recorded on examination. Job titles were merged into occupational groups of workers performing similar work tasks and having similar training. Occupational biomechanical exposure estimates were assigned to each occupational group with a job exposure matrix (JEM) developed for the study. Negative binomial models were used to assess the relative risks for each biomechanical exposure and the sums of highly correlated biomechanical exposures. Surgical treatment of UNE was determined via a linkage with the Swedish Hospital Outpatient Surgery Register. RESULTS: There were 555 cases of surgically treated UNE within the cohort. Workers exposed to forceful hand-grip factors had a 1.4-fold higher relative risk (95% CI 1.18–1.63) of undergoing surgical treatment for UNE compared to unexposed workers. Occupational groups comprising workers exposed to forceful hand-grip work showed the highest risks for UNE and included concrete workers, floor layers, ground preparatory workers, rock blasters, and sheet-metal workers. CONCLUSION: Forceful hand-grip work increases the risk for surgically treated ulnar nerve entrapment.

Objective The aim of this study was to explore the association between occupational exposure to diesel exhaust and polycyclic aromatic hydrocarbons (PAH), respectively, and breast cancer subtypes. Methods The study included 38 375 women <70 years with incident breast cancer, identified in the Danish Cancer Registry, and 5 breast cancer-free controls per case who were randomly selected from the Danish Civil Registration System and matched on year of birth. Full employment history was obtained for all study subjects from a nationwide pension fund, and exposure to diesel exhaust and PAH was assessed using a job exposure matrix. Conditional logistic regression was used for estimation of odds ratios (OR) with adjustment for reproductive factors and socioeconomic status. Results No noteworthy associations were observed for overall breast cancer in women exposed to diesel exhaust. However, diesel exhaust modestly elevated the risk of estrogen receptor negative breast tumors before age 50 [OR 1.26, 95% confidence interval (CI) 1.09-1.46]. Duration- and dose-response relationships were further observed for this subtype in this age group. No notable risk patterns were generally observed for PAH exposure. Conclusion Occupational exposure to diesel exhaust may increase the risk of early-onset estrogen receptor negative breast tumors in women. Future studies exploring this association are warranted. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to study mortality due to cardiovascular disease as well as total mortality, among female industrial workers, and the association to occupational noise and shift work. Methods: Women from cohorts of soft tissue paper mills (N = 3013) and pulp and paper mills (N = 1483) were merged into one cohort. Job exposure matrices were developed and used for classification of shift work and noise exposure. Every year was classified as shift work excluding nights or shift work including nights. Noise was classified into seven 5 dB(A) bins from < 75 to ≥ 100 dB(A). Mortality from cardiovascular diseases and total mortality during 1956–2013 was calculated as a standardized mortality ratio (SMR) with 95% confidence interval (CI) using the female general population as a reference. Results: Fatal myocardial infarctions (N = 144) were increased in the total cohort, SMR 1.20 (95% CI 1.01–1.41) but not total mortality. The SMR for myocardial infarction for women exposed to noise ≥ 90 dB(A) for > 10 years was 1.41 (95% CI 1.02–1.89) and for those exposed to night shifts > 10 years, 1.33 (95% CI 0.91–1.89). Shift workers without nights ≤ 65 years, with noise exposure ≥ 90 dB(A), had SMR 2.41 (95% CI 1.20–4.31) from myocardial infarction. There was no increased mortality from cerebrovascular disease. Conclusions: Female paper mill workers had an increased mortality from acute myocardial infarction, especially before retirement age, when exposed to noise ≥ 90 dB(A) and with long-time employment. Exposure to shift work and noise usually occurred concurrently. [ABSTRACT FROM AUTHOR]

The audiovisual entertainment industry has entered a race to find the video encoder offering the best Rate/Distortion (R/D) performance for high-quality high-definition video content. The challenge consists in providing a moderate to low computational/hardware complexity encoder able to run Ultra High-Definition (UHD) video formats of different flavours (360°C, AR/VR, etc.) with state-of-the-art R/D performance results. It is necessary to evaluate not only R/D performance, a highly important feature, but also the complexity of future video encoders. New coding tools offering a small increase in R/D performance at the cost of greater complexity are being advanced with caution. We performed a detailed analysis of two evolutions of High Efficiency Video Coding (HEVC) video standards, Joint Exploration Model (JEM) and Versatile Video Coding (VVC), in terms of both R/D performance and complexity. The results show how VVC, which represents the new direction of future standards, has, for the time being, sacrificed R/D performance in order to significantly reduce overall coding/decoding complexity. [ABSTRACT FROM AUTHOR]

Objectives Exposure to environmental noise has been associated with an increased risk of cardiovascular diseases and diabetes, but evidence for occupational noise is limited and conflicting, especially related to pregnancy outcomes. This study aimed to evaluate the association of occupational noise exposure with hypertensive disorders of pregnancy (HDP) and gestational diabetes. Methods Our population-based cohort study utilized data on 1 109 516 singletons born to working mothers in Sweden between 1994-2014 from the Medical Birth Register and the Longitudinal Integration Database for Health Insurance and Labor Market Studies. Noise exposure came from a job exposure matrix (JEM) in five categories <70, 70-74, 75-80, 80-85, >85 dB(A). Relative risks (RR), adjusted for confounders and other job exposures, were calculated by modified Poisson regressions for the full sample and a subsample of first-time mothers reporting full-time work. Results Exposure to 80-85 dB(A) of noise was associated with an increased risk of all HDP [RR 1.12, 95% confidence interval (CI) 1.05-1.18] and preeclampsia alone (RR 1.14, 95% CI 1.07-1.22) in the full sample. Results were similar for first-pregnancy, full-time workers. Exposure to >85 dB(A) of noise was also associated with an increased risk of gestational diabetes (RR 1.57, 95% CI 1.10-2.24) in the analysis restricted to first-time mothers working full-time. Conclusion In this study, exposure to noise was associated with an increased risk for HDP and gestational diabetes, particularly in first-time mothers who work full-time. Further research is needed to confirm findings and identify the role of hearing protection on this association so prevention policies can be implemented. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this case–control study was to assess the effect of night-shift work on the risk of hematological cancers. METHODS: The study included 39 371 leukemia, 56 713 non-Hodgkin lymphoma, 9322 Hodgkin lymphoma, and 26 188 multiple myeloma cases diagnosed between 1961 and 2005 in Finland, Sweden, and Iceland. Five controls for each case were selected from the Nordic Occupational Cancer Study (NOCCA) cohort, matched by year of birth, sex and country. Night-shift exposure was assessed by using the NOCCA job-exposure matrix (JEM). Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated from conditional logistic regression models. RESULTS: Overall, night work was not associated with a risk of hematological cancers. We observed a small but non-significantly increased risk for leukemia (OR 1.07, 95% CI 0.99–1.16), especially for acute myeloid leukemia (OR 1.15, 95% CI 0.97–1.36) among workers exposed to a high level of cumulative night work exposure. Night work exposure was not associated with lymphatic cancers and multiple myeloma. CONCLUSION: This study did not support associations between night-shift work and hematological cancers.

OBJECTIVES: The etiology of male breast cancer (MBC) is largely unknown but a causal role of exposure to organic solvents has been suggested. Previous studies on occupational risk factors of breast cancer were often restricted to women who are frequently exposed to lower levels and at a lower frequency than men. We investigated the association between MBC and occupational exposure to petroleum and oxygenated and chlorinated solvents in a multicenter case-control study of rare cancers in Europe. METHODS: The study included 104 MBC cases and 1901 controls. Detailed lifetime work history was obtained during interviews, together with sociodemographic characteristics, medical history and lifestyle factors. Occupational exposures to solvents were estimated from a job-exposure matrix. Odds ratios (OR) and their 95% confidence intervals (CI) were calculated using unconditional logistic regression models. RESULTS: Lifetime cumulative exposure to trichloroethylene >23.9 ppm years was associated with an increased MBC risk, compared to non-exposure [OR (95% CI): 2.1 (1.2–4.0); P trend

The proportion of video traffic on the internet is expected to reach 82% by 2022, mainly due to the increasing number of consumers and the emergence of new video formats with more demanding features (depth, resolution, multiview, 360, etc.). Efforts are therefore being made to constantly improve video compression standards to minimize the necessary bandwidth while retaining high video quality levels. In this context, the Joint Collaborative Team on Video Coding has been analyzing new video coding technologies to improve the compression efficiency with respect to the HEVC video coding standard. A software package known as the Joint Exploration Test Model has been proposed to implement and evaluate new video coding tools. In this work, we present parallel versions of the JEM encoder that are particularly suited for shared memory platforms, and can significantly reduce its huge computational complexity. The proposed parallel algorithms are shown to achieve high levels of parallel efficiency. In particular, in the All Intra coding mode, the best of our proposed parallel versions achieves an average efficiency value of 93.4%. They also had high levels of scalability, as shown by the inclusion of an automatic load balancing mechanism.

Objectives The study aims to explore the prospective associations of the psychosocial work exposures of the job strain model with cardiovascular mortality, including mortality for ischemic heart diseases (IHD) and stroke, using various time-varying exposure measures in the French working population of employees. Methods The study was based on a cohort of 798 547 men and 697 785 women for which job history data from 1976 to 2002 were linked to mortality data and causes of death from the national death registry. Psychosocial work exposures from the validated job strain model questionnaire were assessed using a job-exposure matrix (JEM). Three time-varying measures of exposure were studied: current, cumulative, and recency-weighted cumulative exposure. Cox proportional hazards models were used to examine the associations between psychosocial work exposures and cardiovascular mortality. Results Within the 1976-2002 period, there were 19 264 cardiovascular deaths among men and 6181 among women. Low decision latitude, low social support, job strain, iso-strain, passive job, and high strain were associated with cardiovascular mortality. Most of these associations were also observed for IHD and stroke mortality. The comparison between the different exposure measures suggested that current exposure may be more important than cumulative (or past) exposure. The population fractions of cardiovascular mortality attributable to job strain were 5.64% for men and 6.44% for women. Conclusions Psychosocial work exposures of the job strain model may play a role in cardiovascular mortality. The estimated burden of cardiovascular mortality associated with these exposures underlines the need for preventive policies oriented toward the psychosocial work environment. [ABSTRACT FROM AUTHOR]

Objectives This study aimed to examine the association between job strain and incident coronary heart disease (CHD) in Denmark, while accounting for changes of job strain. Methods We included all employees residing in Denmark in 2000, aged 30-59 years with no prevalent CHD (N=1 660 150). We determined exposure to job strain from 1996-2009 using a job exposure matrix (JEM) with annual updates. Follow-up for incident CHD was from 2001-2010 via linkage to health records. We used Cox regression to calculate hazard ratios (HR) and 95% confidence intervals (CI) for the association between job strain and incident CHD. Results During 16.1 million person-years, we identified 24 159 incident CHD cases (15.0 per 10 000 personyears). After adjustment for covariates, job strain in 2000 predicted onset of CHD during a mean follow-up of 9.71 years (HR 1.10, 95% CI 1.07-1.13). When analyzing changes in job strain from one year to the next and CHD in the subsequent year, persistent job strain (HR 1.07, 95% CI 1.03-1.10), onset of job strain (HR 1.20, 95% CI 1.12-1.29) and removal of strain (HR 1.20, 95% CI 1.12-1.28) were associated with higher CHD incidence compared to persistent no job strain. Associations were similar among men and women. Conclusions Job strain is associated with a higher risk of incident CHD in Denmark. As we used a JEM, we can rule out reporting bias. However, under- or overestimation of associations is possible due to non-differential misclassification of job strain and residual confounding by socioeconomic position. [ABSTRACT FROM AUTHOR]

Block partition structure is a critical module in video coding scheme to achieve significant gap of compression performance. Under the exploration of the future video coding standard, named Versatile Video Coding (VVC), a new Quad Tree Binary Tree (QTBT) block partition structure has been introduced. In addition to the QT block partitioning defined in High Efficiency Video Coding (HEVC) standard, new horizontal and vertical BT partitions are enabled, which drastically increases the encoding time compared to HEVC. In this paper, we propose a lightweight and tunable QTBT partitioning scheme based on a Machine Learning (ML) approach. The proposed solution uses Random Forest classifiers to determine for each coding block the most probable partition modes. To minimize the encoding loss induced by misclassification, risk intervals for classifier decisions are introduced in the proposed solution. By varying the size of risk intervals, tunable trade-off between encoding complexity reduction and coding loss is achieved. The proposed solution implemented in the JEM-7.0 software offers encoding complexity reductions ranging from 30% to 70% in average for only 0.7% to 3.0% Bjøntegaard Delta Rate (BD-BR) increase in Random Access (RA) coding configuration, with very slight overhead induced by Random Forest. The proposed solution based on Random Forest classifiers is also efficient to reduce the complexity of the Multi-Type Tree (MTT) partitioning scheme under the VTM-5.0 software, with complexity reductions ranging from 25% to 61% in average for only 0.4% to 2.2% BD-BR increase. [ABSTRACT FROM AUTHOR]

Objective Albeit a pivotal risk for the development of hand eczema (HE), the exposure-response relationship between wet work and HE remains to be further investigated. Knowledge on exposure-response is important regarding preventive measures, medico-legal regulations and job-counseling. Recently, a job-exposure matrix (JEM) for wet work was developed, providing information on the likelihood of wet work. By combining the JEM with data on HE we aimed to investigate the relationship between extent of wet work and HE. Methods This study is a case-referent study including patients registered in the National Database of Contact Allergy, Denmark, and comprises data on sex, age, atopic dermatitis, HE, face eczema and patch testing results. Patients with HE served as cases and patients with facial eczema served as referents. Information on profession was retrieved from the DOC*X database in accordance with the DISCO-88 classification system. A wet-workspecific JEM provides - for each profession - an estimate for (i) the likelihood of wet work lasting ≥2 hours/day and (ii) the average number of hours of wet work per day. Results After two hours of wet hands and glove wear, the odds ratio (OR) was 3.49 and 3.19, respectively, for females and 2.41 and 1.82, respectively, for males. Females had a higher risk of HE than males with probability of wet hands <75% (OR 2.34, 95% CI 2.12-2.58 compared to males 1.68, 95% CI 1.22-2.31) and regarding glove wear at all exposure levels. Conclusion Our data confirms a close association between wet work and HE. Exposure lasting less than the current definition of wet work (having wet hands for ≥2 hours per day) may be of importance. [ABSTRACT FROM AUTHOR]