Study design of National Surveillance of the Work Environment of Employees in Denmark (NASWEED): Prospective cohort with register follow-up.

AIM: The aim is to report the design and baseline data of the 'National Surveillance of the Work Environment of Employees in Denmark' study (NASWEED). METHODS: NASWEED consist of (a) bi-annual cross-sectional samples, based on probability samples of wage earners of the general working population in Denmark from 2021 onwards (surveillance), (b) a prospective cohort of all previous respondents every two years (epidemiology, questionnaire follow-up) and (c) longitudinal follow-up in Danish registers about work and health (epidemiology, register follow-up). Between February and May 2021, a stratified (38 occupational industries) probability sample of 63,391 Danish residents aged 15-69 years who were employed for at least 34 hours per month received an invitation to participate, of whom 30,099 (47.5%) completed the questionnaire, 897 (1.4%) partially completed the questionnaire and 32,395 (51.1%) did not respond. Baseline was completed in June 2021. NASWEED covers various topics about the work environment (psychosocial, ergonomic, chemical, biological, safety, accidents, working from home, etc), health behaviours and somatic and mental health-related conditions. Statistical analyses will mainly build on survey procedures with model-assisted weights to ensure that the sample will yield representative estimates of the general working population. DISCUSSION: NASWEED will monitor the development of the work environment and health in Denmark until 2030. The survey data will be included in epidemiological studies with repeated measurement of the work environment, health variables and covariates, and follow-ups in national registers to investigate the prospective association in the years and decades to come between the work environment and workers' health and labour market participation.

Is fatigue after work a barrier for leisure-time physical activity? Cross-sectional study among 10,000 adults from the general working population.

AIM: In spite of the many health-related benefits of regular physical activity, fatiguing work may be a barrier to performing leisure-time physical activity. This study investigates the association between work-related fatigue and the duration of low- and high-intensity leisure-time physical activity in workers with sedentary and physically demanding jobs. METHODS: From the 2010 round of the Danish Work Environment Cohort Study, currently employed wage earners from the general working population ( N=10,427) replied to questions about work-related fatigue (predictor) and duration of low- and high-intensity leisure-time physical activity (outcome). Associations were modelled using general linear models controlling for various confounders. RESULTS: Among workers with physically demanding jobs, higher levels of work-related fatigue were associated with gradually lower levels of leisure-time physical activity - for low, moderate and high levels of work-related fatigue the duration of high-intensity leisure-time physical activity was 133 (95% confidence interval (CI) 127-178), 134 (95% CI 109-160) and 113 (95% CI 86-140) min per week, respectively (trend test p<0.001). The duration of high-intensity leisure-time physical activity was lower among older workers (≥50 years) compared to younger workers (<50 years) (132 ± 126 vs 168 ± 150 min per week) ( p<0.0001). CONCLUSIONS: The duration of high-intensity leisure-time physical activity gradually decreases with increased work-related fatigue in workers with physically demanding jobs. Older workers perform less high-intensity physical activity than younger workers. Workplaces should consider initiatives to allow workers with physically demanding jobs and older workers to perform physical exercise during working hours and thereby increase physical capacity to meet the job demands.

Physical workload and bodily fatigue after work: cross-sectional study among 5000 workers.

BACKGROUND: Persistent bodily fatigue after working days may indicate an imbalance between work demands and capacity of the workers. This study aimed to investigate associations between physical exposures at work and bodily fatigue after work. METHODS: Danish workers with physical work (N=5377) answered questions about various physical exposures during work and bodily fatigue after work in the 2010 round of the Danish Work Environment Cohort Study. Associations were modeled using binary logistic regression controlled for various confounders. RESULTS: Mean age among the younger (<50 years) and older (≥50 years) workers was 36 and 56 years, respectively. Younger and older workers exposed to various physical exposures (e.g. 'bending/twisting the back') for more than a quarter of the workday were more fatigued after work. An exposure-response relationship was observed between the number of physical exposures and bodily fatigue, with odds ratios (OR) for fatigue in the body among younger workers being 1.01 (95%CI 0.63-1.63), 1.59 (95%CI 1.01-2.50), 2.37 (95%CI 1.54-3.66) and 2.84 (95%CI 1.85-5.36) for 1, 2, 3 and ≥4 types of combined physical exposures, respectively. Correspondingly, for older workers, ORs were 1.95 (95%CI 1.09-3.51), 4.06 (95%CI 2.32-7.12), 4.10 (95%CI 2.28-7.37) and 4.90 (95%CI 2.72-8.82) for 1, 2, 3 and ≥4 exposures, respectively. CONCLUSION: While some of the single factor exposures were associated with increased bodily fatigue, the most marked associations were found when summing the number of different exposures. These results indicate that workplaces should focus on the sum of combined physical exposures rather than focusing solely on single exposures.

Association between lifestyle and musculoskeletal pain: cross-sectional study among 10,000 adults from the general working population.

BACKGROUND: Work-related musculoskeletal pain is a major cause of work disability and sickness absence. While pain is a multifactorial phenomenon being influenced by work as well as lifestyle, less is known about the association between specific lifestyle factors and the type of musculoskeletal pain. The aim of the study was to investigate if a dose-response association existed between lifestyle factors and musculoskeletal pain intensity in the low back and neck-shoulder. METHODS: Currently employed wage earners (N = 10,427) replied in 2010 to questions about work environment, lifestyle and health. Logistic regression analyses adjusted for various confounders tested the association of alcohol intake, physical activity, fruit and vegetable intake, and smoking (explanatory variables) with low back pain and neck-shoulder pain intensity (outcomes variables, scale 0-9, where ≥4 is high pain). RESULTS: The minimally adjusted model found that physical activity and fruit and vegetable intake were associated with lower risk of musculoskeletal pain, while smoking was associated with higher risk of musculoskeletal pain. In the fully adjusted model, physical activity ≥5 h per week was associated with lower risk of low back pain and neck-shoulder pain with risk ratios (RR) of 0.95 (95% CI 0.90-1.00) and 0.90 (95% CI 0.82-0.99), respectively. No association was found between alcohol intake and pain. CONCLUSION: Being physically active associated with lower risk of having musculoskeletal pain, while smoking habits and healthy eating were associated with higher pain when adjusting for age and gender. Considering the continuously increasing retirement age in many societies, initiatives to promote healthy habits should still be a political priority to help the workers to stay healthy and cope to their work.

Cardiorespiratory fitness and death from cancer: a 42-year follow-up from the Copenhagen Male Study.

OBJECTIVES: Poor cardiorespiratory fitness (CRF) is associated with death from cancer. If follow-up time is short, this association may be confounded by subclinical disease already present at the time of CRF assessment. This study investigates the association between CRF and death from cancer and any cause with 42 years and 44 years of follow-up, respectively. SETTING, PARTICIPANTS AND MAIN OUTCOME MEASURES: Middle-aged, employed and cancer-free Danish men from the prospective Copenhagen Male Study, enrolled in 1970-1971, were included. CRF (maximal oxygen consumption (VO2max)) was estimated using a bicycle ergometer test and analysed in multivariable Cox models including conventional risk factors, social class and self-reported physical activity. Death from cancer and all-cause mortality was assessed using Danish national registers. Follow-up was 100% complete. RESULTS: In total, 5131 men were included, mean (SD) age 48.8 (5.4) years. During 44 years of follow-up, 4486 subjects died (87.4%), 1527 (29.8%) from cancer. In multivariable models, CRF was highly significantly inversely associated with death from cancer and all-cause mortality ((HR (95% CI)) 0.83 (0.77 to 0.90) and 0.89 (0.85 to 0.93) per 10 mL/kg/min increase in estimated VO2max, respectively). A similar association was seen across specific cancer groups, except death from prostate cancer (1.00 (0.82 to 1.2); p=0.97; n=231). The associations between CRF and outcomes remained essentially unchanged after excluding subjects dying within 10 years (n=377) and 20 years (n=1276) of inclusion. CONCLUSIONS: CRF is highly significantly inversely associated with death from cancer and all-cause mortality. The associations are robust for exclusion of subjects dying within 20 years of study inclusion, thereby suggesting a minimal influence of reverse causation.

Low back pain patterns over one year among 842 workers in the DPhacto study and predictors for chronicity based on repetitive measurements.

BACKGROUND: Low back pain (LBP) occurrence and intensity are considered to fluctuate over time, requiring frequent repetitive assessments to capture its true time pattern. Text messages makes frequent reporting of LBP feasible, which enables investigation of 1) the time pattern of LBP, and 2) predictors for having a continued high (chronic) level of LBP over longer periods of time. However, this has not previously been investigated in a larger working population. The aim of this study was to examine these two aspects in a working population of 842 workers with repetitive measurements of LBP over one year. METHODS: There were 842 workers from 15 companies in the DPhacto study participating in this study. Demographic, work- and health-related factors, and back endurance were measured at baseline, while 14 monthly repeated text message assessments of LBP intensity were prospectively collected. A factor analysis was used to cluster different time-patterns of LBP, and defining the group of participants with chronic LBP. A multi-adjusted logistic regression analysis was performed to investigate baseline predictors for chronic LBP. RESULTS: The factor analysis revealed two dimensions of the time pattern of LBP, defined as the LBP intensity and LBP variation, respectively. A Visual Pain Mapping was formed based on the combination of the two pain dimensions, classifying the time-patterns of LBP into four categories: (1) low intensity and low variation, (2) low intensity and high variation, (3) high intensity and high variation, (4) high intensity and low variation (defined as chronic LBP). Significant baseline predictors for chronic LBP in the fully adjusted model were high baseline LBP (p < 0.01), low workability (p < 0.01), low BMI (p < 0.05), and being a blue-collar worker (vs. white-collar worker) (p < 0.05). CONCLUSION: This study presents a novel classification of the course of LBP based on repetitive measurements over a year, and revealed the predicting factors for chronic LBP based on repetitive measurements in a working population.

Safety interventions for the prevention of accidents at work: A systematic review.

Background: Limited knowledge regarding the relative effectiveness of workplace accident prevention approaches creates barriers to informed decision-making by policy makers, public health practitioners, workplace, and worker advocates. Objectives: The objective of this review was to assess the effectiveness of broad categories of safety interventions in preventing accidents at work. The review aims to compare effects of safety interventions to no intervention, usual activities, or alternative intervention, and if possible, to examine which constituent components of safety intervention programs contribute more strongly to preventing accidents at work in a given setting or context. Date Sources: Studies were identified through electronic bibliographic searches, government policy databanks, and Internet search engines. The last search was carried out on July 9, 2015. Gray literature were identified by searching OSH ROM and Google. No language or date restrictions were applied. Searches done between February and July of 2015 included PubMed (1966), Embase (1980), CINAHL (1981), OSH ROM (NIOSHTIC 1977, HSELINE 1977, CIS-DOC 1974), PsycINFO (1806), EconLit (1969), Web of Science (1969), and ProQuest (1861); dates represent initial availability of each database. Websites of pertinent institutions (NIOSH, Perosh) were also searched. Study Eligibility Criteria Participants and Interventions: Included studies had to focus on accidents at work, include an evaluation of a safety intervention, and have used injuries at work, or a relevant proxy, as an outcome measure. Experimental, quasi-experimental, and observational study designs were utilized, including randomized controlled trials (RCTs), controlled before and after (CBA) studies, and observational designs using serial measures (interrupted time series, retrospective cohort designs, and before and after studies using multiple measures). Interventions were classified by approach at the individual or group level, and broad categories based on the prevention approach including modification of: Attitudes (through information and persuasive campaign messaging).Behaviors (through training, incentives, goal setting, feedback/coaching).Physiological condition (by physical training).Climate/norms/culture (by coaching, feedback, modification of safety management/leadership).Structural conditions (including physical environment, engineering, legislation and enforcement, sectorial-level norms). When combined approaches were used, interventions were termed "multifaceted," and when an approach(es) is applied to more than one organizational level (e.g., individual, group, and/or organization), it is termed "across levels." Study Appraisal and Synthesis Methods: Narrative report review captured industry (NACE), work setting, participant characteristics, theoretical basis for approach, intervention fidelity, research design, risk of bias, contextual detail, outcomes measures and results. Additional items were extracted for studies with serial measures including approaches to improve internal validity, assessments of reasonable statistical approaches (Effective Practice of Organization of Care [EPOC] criteria) and overall inference. Random-effects inverse variance weighted meta-analytic methods were used to synthesize odds ratios, rate ratios, or standardized mean differences for the outcomes for RCT and CBA studies with low or moderate levels of heterogeneity. For studies with greater heterogeneity and those using serial measures, we relied on narrative analyses to synthesize findings. Results: In total 100 original studies were included for synthesis analysis, including 16 RCT study designs, 30 CBA study designs, and 54 studies using serial measures (ITS study designs). These studies represented 120 cases of safety interventions. The number of participants included 31,971,908 individuals in 59 safety interventions, 417,693 groups/firms in 35 safety interventions, and 15,505 injuries in 17 safety interventions. Out of the 59 safety interventions, two were evaluating national prevention measures, which alone accounted for 31,667,110 individuals. The remaining nine safety interventions used other types of measures, such as safety exposure, safety observations, gloves or claim rates. Strong evidence supports greater effects being achieved with safety interventions directed toward the group or organization level rather than individual behavior change. Engineering controls are more effective at reducing injuries than other approaches, particularly when engineered changes can be introduced without requiring "decision-to-use" by workplaces. Multifaceted approaches combining intervention elements on the organizational level, or across levels, provided moderate to strong effects, in particular when engineering controls were included. Interventions based on firm epidemiologic evidence of causality and a strong conceptual approach were more effective. Effects that are more modest were observed (in short follow-up) for safety climate interventions, using techniques such as feedback or leadership training to improve safety communication. There was limited evidence for a strong effect at medium-term with more intense counseling approaches. Evidence supports regulation/legislation as contributing to the prevention of accidents at work, but with lower effect sizes. Enforcement appears to work more consistently, but with smaller effects. In general, the results were consistent with previous systematic reviews of specific types of safety interventions, although the effectiveness of economic incentives to prevent accidents at work was not consistent with our results, and effectiveness of physiological safety intervention was only consistent to some extent. Limitations: Acute musculoskeletal injuries and injuries from more long-time workplace exposures were not always clearly distinguished in research reports. In some studies acute and chronic exposures were mixed, resulting in inevitable misclassification. Of note, the classification of these events also remains problematic in clinical medicine. It was not possible to conduct meta-analyses on all types of interventions (due to variability in approach, context, and participants). The findings presented for most intervention types are from limited sources, and assessment of publication bias was not possible. These issues are not surprising, given the breadth of the field of occupational safety. To incorporate studies using serial measures, which provide the only source of information for some safety interventions such as legislation, we took a systematic, grounded approach to their review. Rather than requiring more stringent, specific criteria for inclusion of ITS studies, we chose to assess how investigators justified their approach to design and analyses, based on the context in which they were working. We sought to identify measures taken to improve external validity of studies, reasonable statistical inference, as well as an overall appropriate inferential process. We found the process useful and enlightening. Given the new approach, we may have failed to extract points others may find relevant. Similarly, to facilitate the broad nature of this review, we used a novel categorization of safety interventions, which is likely to evolve with additional use. The broad scope of this review and the time and resources available did not allow for contacting authors of original papers or seeking translation of non-English manuscripts, resulting in a few cases where we did not have sufficient information that may have been possible to obtain from the authors. Conclusions and Implications of Key Findings: Our synthesis of the relative effectiveness of workplace safety interventions is in accordance with the Public Health Hierarchy of Hazard Control. Specifically, more effective interventions eliminate risk at the source of the hazard through engineering solutions or the separation of workers from hazards; effects were greater when these control measures worked independently of worker "decision-to-use" at the worksite. Interventions based on firm epidemiological evidence of causality and clear theoretical bases for the intervention approach were more effective in preventing injuries. Less effective behavioral approaches were often directed at the prevention of all workplace injuries through a common pathway, such as introducing safety training, without explicitly addressing specific hazards. We caution that this does not mean that training does not play an essential function in worker safety, but rather that it is not effective in the absence of other efforts. Due to the potential to reach large groups of workers through regulation and enforcement, these interventions with relatively modest effects, could have large population-based effects.

Maternal life and work stressors during pregnancy and asthma in offspring.

BACKGROUND: Maternal stressors during pregnancy are potential risk factors for asthma in offspring. However, previous studies have been limited by the use of self-reported data focusing on stressors either in private life or at work. This study examined the association between maternal stressors both in private life and at work during pregnancy and asthma in offspring. METHODS: In the Danish National Birth Cohort, 75 156 live-born singletons born during 1996-2002 were identified. Maternal information on job title were available around weeks 12-16 of gestation. Data on maternal bereavement, life-threatening illness, suicide attempt and alcohol or drug abuse of a close relative and offspring childhood asthma (3-10 years of age) were obtained from Danish nationwide registers. Maternal psychosocial work stressors (job control, psychological job demands, emotional job demands, work-related violence and threats of work-related violence) were estimated by the use of job-exposure matrices. The association between maternal stress and childhood asthma was analysed in Cox models adjusted for maternal age, comorbidity and parity. RESULTS: Neither private-life nor work stressors were related to onset of asthma in offspring. Separate analyses by parental atopy or onset of asthma in offspring supported the main findings. CONCLUSIONS: This study does not support an elevated risk of childhood asthma related to exposure to stress during pregnancy.

The influence of multiple occupational exposures on absence from work in pregnancy: a prospective cohort study.

Objectives Many women experience absence periods from work during pregnancy. Several single risk factors for absence are identified, whereas the impact of multiple concurrent exposures has been sparsely studied. We hypothesized that the presence of multiple occupational exposures would be associated with an increased risk of absence from work during pregnancy. Methods We included women from the Danish National Birth Cohort (1996-2002), pregnant with one child and working ≥30 hours/week at interview (mean gestational week 17 (standard deviation 4.0); N=50 142). Information about five occupational exposures (job demands, job control, work posture, work shift, lifting) were retrieved from the interview, each assigned values of 0/1, and summed into an index (0-5). The woman's first absence from work (both regular and related to pregnancy) after the interview was available from a nationwide administrative register. We analyzed data with Cox regression using gestational age as the underlying time-variable. Results Few women experienced none of the occupational exposures (3.6%) and most experienced two exposures (34.7%). Only 24.3% of the women were absent from work before gestational week 31. The number of occupational exposures was associated with an increasing risk of absence. The adjusted hazard ratio for absence increased from 1.3 [95% confidence interval (CI) 1.1-1.5] for one exposure to 2.9 (95% CI 2.5-3.3) for four to five exposures compared to no occupational exposure. Conclusion The higher the number of potentially adverse occupational exposures pregnant women experienced, the higher the risk for absence from work during pregnancy.

Musculoskeletal pain in multiple body sites and work ability in the general working population: cross-sectional study among 10,000 wage earners.

Background and aims Musculoskeletal pain may negatively affect work ability, especially when work demands are high and/or physical capacity of the worker is low. This study investigated the association between intensity of musculoskeletal pain in multiple body regions and work ability among young and old workers with sedentary and physical demanding jobs. Methods Currently employed wage earners (n=10,427) replied to questions about pain intensity, work ability, and physical work demands. The odds ratio (OR) for having a lower level of work ability in relation to the physical demands at work were modeled using logistic regression controlled for various confounders. Results The OR for lower work ability increased with higher pain intensity in all regions among workers with sedentary and physical work. The same pattern was observed among workers <50 years and ≥50 years in both work types. The association was quite consistent across age and work activity groups, although it tended to be more pronounced among those with physically demanding work in some of pain regions. Conclusions This study shows that increasing pain intensity in multiple sites of the body is associated with lower work ability. This was seen for both younger and older workers as well as those with sedentary and physical work. Implications Physical workers with multiple-site pain may especially be at increased risk of the consequences of reduced work ability. Therefore, extra attention is needed and this group may benefit from better targeted preventive measures.

Are Insomnia Type Sleep Problems Associated With a Less Physically Active Lifestyle? A Cross-Sectional Study Among 7,700 Adults From the General Working Population.

Background: Sleep problems are common in the general population and negatively affect both private and work life. A vicious circle may exist between poor sleep and an unhealthy lifestyle. For example, poor sleep may drain the energy to do health-promoting physical activity during leisure-time after work. The aim of the present study was to investigate the association between sleep problems and the duration of low- and high-intensity leisure-time physical activity in sedentary and physical workers. Methods: This cross-sectional study employ data from the Danish Work Environment Cohort Study in 2010, where currently employed wage-earners in Denmark on daytime schedule (N = 7,706) replied to questions about sleep quality (cf. the Bergen Insomnia Scale) and participation in low- and high-intensity leisure-time physical activity. Associations were modeled using general linear models controlling for various confounders. Results: Workers with high levels of sleep problems reported less high-intensity leisure-time physical activity. Specifically, the weekly duration of high-intensity leisure-time physical activity was 139 (95%CI 111-168), 129 (95%CI 101-158), and 122 (95%CI 92-151) min in sedentary workers with sleep problems < 1, 1-3, and ≥3 days per week, respectively. The same pattern was observed among physical workers. In sedentary workers ≥50 years, the fully adjusted model showed a weekly duration in high-intensity physical activity during leisure of 122 (95%CI 83-161), 102 (95%CI 64-141), and 90 (95%CI 51-130) among those with sleep problems < 1, 1-3, and ≥3 days per week, respectively. Conclusions: Workers, particularly sedentary older workers, having sleep problems report less high-intensity leisure-time physical activity. These data suggest that a vicious circle may indeed exist between poor sleep and reduced leisure-time physical activity.

Survival of LA-MRSA in Dust from Swine Farms.

Dust is suspected to be an important factor in transmission of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) between pigs and pig farmers and their families. The aim of this study was to determine the rate of decay for Staphylococcus aureus and LA-MRSA in dust from swine farms. Electrostatic dust fall collectors (EDCs) were used for passive sampling of settling airborne dust in 11 stable sections from six swine farms. Extraction, plating, identification, and enumeration of cultivable S. aureus and LA-MRSA from the EDCs were performed after storage for 0-30 days postsampling. The survival of S. aureus was measured in 196 dust samples from all farms, and data were used to estimate the decay constant λ according to a model for exponential decay: N(t) = N0 × e-λt. The number of S. aureus colonies was up to 600-fold higher than the number of LA-MRSA colonies on MRSA selective agar. The data showed a good fit to the model (λ = 0.13, r2 = 0.86) even with a large difference in initial concentrations of S. aureus between stables. The loads of S. aureus and LA-MRSA in the dust were significantly reduced by storage time, and the half-life was 5 days for both S. aureus and LA-MRSA. In dust samples with high initial concentrations, LA-MRSA and S. aureus could still be cultivated 30 days after sampling. On all farms MRSA isolates belonged to the clonal complex (CC) 398, and at one farm some isolates also belonged to CC30. A screening for other Staphylococcus species in the farm dust revealed 13 different species numerically dominated by Staphylococcus equorum. Based on the exponential decay model, S. equorum had a half-life of 4 days. In conclusion, the presence of MRSA in airborne dust from five of six farms indicates that dust might be an important vehicle for transmission of LA-MRSA. LA-MRSA and S. aureus was found to survive well in farm dust with half-lives of 5 days, and dependent on the initial concentration they could be found in farm dust for weeks. The 99.9% die-off rate was 66 days for LA-MRSA. Thus, farm dust can pose an exposure risk for humans in the farm environment, but also when transported to other environments. On the other hand, the risk will decrease by time. These results provide important knowledge to diminish spread from farm environments to other environments on, e.g., tools or clothing, and in relation to cleaning of emptied LA-MRSA-positive stables.

Combined exposure to lifting and psychosocial strain at work and adverse pregnancy outcomes-A study in the Danish National Birth Cohort.

BACKGROUND: Previous studies have investigated physical and psychosocial job exposures separately in relation to foetal growth. We therefore investigated if occupational lifting and psychosocial job strain interact to affect foetal growth and gestational length. We hypothesised that heavy lifting and high job strain would increase the risk of impacted foetal growth (small or large for gestational age) and preterm birth. METHODS: The cohort included 47,582 pregnancies from the Danish National Birth Cohort (1996-2002), where the woman was pregnant at 22 gestational weeks (GW), expected one child and worked ≥30 hours/week. Information on occupational lifting and psychosocial job strain was derived from an interview (16±3.0 GW). Data to calculate small and large for gestational age (SGA/LGA) and gestational length was retrieved from the Medical Birth Register. Interaction between lifting and job strain (Karasek's model) was analysed by multinomial logistic regression. RESULTS: Overall, the adjusted regression analysis showed statistically significant interaction between lifting and job strain for SGA and LGA. For each additional 250 kg lifted/day, high strain women (high Demand/low Control) had increased odds of giving birth to a LGA-child (OR = 1.15; 95% CI 1.06-1.26), whereas women in the active group (high Demand/high Control) had increased odds of giving birth to a SGA child (OR = 1.12; 95% CI 1.03-1.23). When women lifting ≤1000 kg/day were excluded in the sensitivity analyses the interaction between lifting and job strain became insignificant. No interaction of lifting and job strain was found for gestational length. CONCLUSIONS: The main findings may give some support to our hypothesis, as lifting in combination high with job strain increased the risk of giving birth to a LGA child. This finding was, however, not supported in the sensitivity analysis and no association of the interaction was found relative to gestational length.

Is questionnaire-based sitting time inaccurate and can it be improved? A cross-sectional investigation using accelerometer-based sitting time.

OBJECTIVES: To investigate the differences between a questionnaire-based and accelerometer-based sitting time, and develop a model for improving the accuracy of questionnaire-based sitting time for predicting accelerometer-based sitting time. METHODS: 183 workers in a cross-sectional study reported sitting time per day using a single question during the measurement period, and wore 2 Actigraph GT3X+ accelerometers on the thigh and trunk for 1-4 working days to determine their actual sitting time per day using the validated Acti4 software. Least squares regression models were fitted with questionnaire-based siting time and other self-reported predictors to predict accelerometer-based sitting time. RESULTS: Questionnaire-based and accelerometer-based average sitting times were ≈272 and ≈476 min/day, respectively. A low Pearson correlation (r=0.32), high mean bias (204.1 min) and wide limits of agreement (549.8 to -139.7 min) between questionnaire-based and accelerometer-based sitting time were found. The prediction model based on questionnaire-based sitting explained 10% of the variance in accelerometer-based sitting time. Inclusion of 9 self-reported predictors in the model increased the explained variance to 41%, with 10% optimism using a resampling bootstrap validation. Based on a split validation analysis, the developed prediction model on ≈75% of the workers (n=132) reduced the mean and the SD of the difference between questionnaire-based and accelerometer-based sitting time by 64% and 42%, respectively, in the remaining 25% of the workers. CONCLUSIONS: This study indicates that questionnaire-based sitting time has low validity and that a prediction model can be one solution to materially improve the precision of questionnaire-based sitting time.

A multifaceted workplace intervention for low back pain in nurses' aides: a pragmatic stepped wedge cluster randomised controlled trial.

This study established the effectiveness of a workplace multifaceted intervention consisting of participatory ergonomics, physical training, and cognitive-behavioural training (CBT) for low back pain (LBP). Between November 2012 and May 2014, we conducted a pragmatic stepped wedge cluster randomised controlled trial with 594 workers from eldercare workplaces (nursing homes and home care) randomised to 4 successive time periods, 3 months apart. The intervention lasted 12 weeks and consisted of 19 sessions in total (physical training [12 sessions], CBT [2 sessions], and participatory ergonomics [5 sessions]). Low back pain was the outcome and was measured as days, intensity (worst pain on a 0-10 numeric rank scale), and bothersomeness (days) by monthly text messages. Linear mixed models were used to estimate the intervention effect. Analyses were performed according to intention to treat, including all eligible randomised participants, and were adjusted for baseline values of the outcome. The linear mixed models yielded significant effects on LBP days of -0.8 (95% confidence interval [CI], -1.19 to -0.38), LBP intensity of -0.4 (95% CI, -0.60 to -0.26), and bothersomeness days of -0.5 (95% CI, -0.85 to -0.13) after the intervention compared with the control group. This study shows that a multifaceted intervention consisting of participatory ergonomics, physical training, and CBT can reduce LBP among workers in eldercare. Thus, multifaceted interventions may be relevant for improving LBP in a working population.