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Occupational noise exposure is a known risk factor for hearing loss and also adverse cardiovascular effects have been suggested. A job exposure matrix (JEM) would enable studies of noise and health on a large scale. The objective of this study was to create a quantitative JEM for occupational noise exposure assessment of the general working population. Between 2001–2003 and 2009–2010, we recruited workers from companies within the 10 industries with the highest reporting of noise-induced hearing loss according to the Danish Working Environment Authority and in addition workers of financial services and children day care to optimize the range in exposure levels. We obtained 1343 personal occupational noise dosimeter measurements among 1140 workers representing 100 different jobs according to the Danish version of the International Standard Classification of Occupations 1988 (DISCO 88). Four experts used 35 of these jobs as benchmarks and rated noise levels for the remaining 337 jobs within DISCO 88. To estimate noise levels for all 372 jobs, we included expert ratings together with sex, age, occupational class, and calendar year as fixed effects, while job and worker were included as random effects in a linear mixed regression model. The fixed effects explained 40% of the total variance: 72% of the between-jobs variance, −6% of the between-workers variance and 4% of the within-worker variance. Modelled noise levels showed a monotonic increase with increasing expert score and a 20 dB difference between the highest and lowest exposed jobs. Based on the JEM estimates, metal wheel-grinders were among the highest and finance and sales professionals among the lowest exposed. This JEM of occupational noise exposure can be used to prioritize preventive efforts of occupational noise exposure and to provide quantitative estimates of contemporary exposure levels in epidemiological studies of health effects potentially associated with noise exposure.

The objective of the present project is to explore the association between maternal stress, including stress both at work and in private life using independent measures of exposure, and measurements of asthma in their children. Further, we will investigate whether sex of the offspring modifies the association. The quality of earlier studies varies considerably. One of the most important methodological problems is the quality of exposure assessment including the fact that existing studies often only assess the effects of either stress at work or stress in private life and therefore fail to account for the multiple stressors that are typically faced in life. The proposed project provides unique opportunities to meet the challenges of the existing studies by addressing the hypotheses in a large population-based cohort, assessing maternal stress during pregnancy both at work and in private life with independent information about both exposures and outcome. The present study protocol therefore gives a detailed description of the data material, inclusion criteria, statistical models, hypotheses and test criteria for a study of maternal stress at work and in private life during pregnancy and childhood asthma in the offspring. In accordance with recognised rules of good scientific and statistical practice; the protocol is public available before the exposure data of the study are linked to the outcome data.

Working in shifts or having irregular working hours is frequent. Shift work and in particular night shifts may increase the risk of disease. Further, studies suggest that shift workers have a higher level of sickness absence than day workers. However, research on the impact of shift work on the risk of sickness absence is sparse, and there is a need for high-quality research including detailed and precise information on shift work. The present study protocol describes the methods of two studies with the aims to study: a) if exposure to night shift prospectively predicts sickness absence of different durations and b) if working hour characteristics e.g. time of day and time between shifts predict sickness absence. The study population is a subpopulation of the Danish Working Hour Database (DWHD); which is created from administrative payroll data of employees from the public sector within the five Danish administrative regions from the period 2007-2013.

The understanding of the impact of shift work and long working hours on the risk of injuries remains incomplete. Many of the existing studies include small sample sizes, unique industries, only men etc. limiting the generalisability of the findings. The present study protocol therefore presents the aims, hypotheses, material and methods for studies of long working hours or night work on the risk of hospital treatment or death due to injuries when taking gender, age, industry, and socioeconomic status into account.

Mental distress has often been suggested as a cause of unexplained infertility. However, the causal direction may well be from infertility to distress, and prospective data are needed. We therefore followed 393 couples, who were planning their first pregnancy, with prospective collection of information on distress from termination of birth control until pregnancy for a maximum of six menstrual cycles. The analyses included 1,475 menstrual cycles, and mental distress was measured in each cycle by the General Health Questionnaire (GHQ). Urine samples from each period of vaginal bleeding were analyzed for human chorionic gonadotrophic hormone, indicating early embryonal loss. We found that for cycles with the highest distress score (GHQ score above the 80 percentile) the probability of conception per cycle was 12.8% compared to 16.5% in other cycles (adjusted OR 0.6; 95% CI 0.4-1.0). The effect of distress was almost exclusively found among women with long menstrual cycles (OR 0.1; 95% CI 0.01-0.4 and OR 0.9; 0.5-1.4 for women with cycles > or = 35 and

no. 024-2Scientific program page 112