Intensity of occupational physical activity in blue-collar workers: do self-reported rating and device-worn measurements agree?

PURPOSE: High intensity occupational physical activity (OPA) seem to aggravate health and increase risk of sick leave and early retirement. Most intensity of OPA monitoring has been self-reported, e.g. by rating of perceived exertion (RPE). However, no studies have investigated the precision and risk of bias in RPE reporting during free-living OPA. This study investigated the agreement between OPA intensity in percentage of the heart rate reserve (%HRR) estimated from RPE and device-measured heart rate (HR), and potential bias factors on this agreement. METHODS: The CR10 scale measured RPE at work. The Actiheart monitor measured HR during 24-h a day for 2-4 days. Both RPE and device-worn HR were converted to %HRR. The difference between both %HRR and their limits of agreement was determined in a Bland Altman plot. To detect bias factors, the difference between both %HRR was regressed on age, sex, cardiorespiratory fitness, occupational lifting, medication, consequences of musculoskeletal disorders and the interactions between these factors with device-work %HRR. RESULTS: Six hundred and twenty-three participants were included in the analysis. Mean difference between RPE-based and device-worn %HRR was 54.6% (SD 19.5). The limits of agreement were wide (11.6-90.1%HRR). Age (0.48%HRR, 95% CI 0.18-0.79) occupational lifting (9.84%HRR, 95% CI 3.85-15.83) and cardiorespiratory fitness (0.41%HRR, 95% CI 0.03-0.79) significantly biased the agreement between the estimations of OPA intensity. CONCLUSION: RPE overestimated OPA intensity, and was biased by several factors. Device-worn %HRR should be preferred when evaluating OPA intensity among workers with physically demanding jobs.

Day-to-day pattern of work and leisure time physical behaviours: are low socioeconomic status adults couch potatoes or work warriors?

BACKGROUND: Most studies on day-to-day patterns of physical behaviours (i.e. physical activities and sedentary behaviour) are based on adults with high socioeconomic status (SES) and without differentiating between work and leisure time. Thus, we aimed to characterise the day-to-day leisure time physical behaviours patterns among low SES adults and investigate the influence of work physical behaviours. METHODS: This cross-sectional study included 963 adults from low SES occupations (e.g. manufacturing, cleaning and transportation). The participants wore accelerometers for 1-7 days to measure physical behaviours during work and leisure time, expressed as time-use compositions consisting of time spent sedentary, standing or being active (walking, running, stair climbing, or cycling). Compositional multivariate multilevel models were used to regress daily leisure time-use composition against work time-use compositions. Interaction between weekday and (1) type of day, (i.e., work/non-work) and (2) the work time-use composition were tested. Compositional isotemporal substitution was used to interpret the estimates from the models. RESULTS: Each weekday, workers consistently spent most leisure time being sedentary and most work time standing. Leisure time physical behaviours were associated with type of day (p < 0.005, more sedentary on workdays vs. non-workdays), weekday (p < 0.005, more sedentary on Friday, Saturday and Sunday), standing work (p < 0.005, more sedentary and less standing and active leisure time on Sunday), and active work (p < 0.005, less sedentary and more standing and active leisure time on Sunday). Sedentary leisure time increased by 18 min, while standing and active leisure time decreased by 11 and 7 min, respectively, when 30 min were reallocated to standing at work on Sunday. Conversely, sedentary leisure time decreased by 25 min, and standing and active leisure time increased by 15 and 10 min, respectively, when 30 min were reallocated to active time at work on Sunday. CONCLUSIONS: While low SES adults' leisure time was mostly sedentary, their work time was predominantly standing. Work physical behaviours differently influenced day-to-day leisure time behaviours. Thus, public health initiatives aiming to change leisure time behaviours among low SES adults should consider the influence of work physical behaviours.

Movement behavior profiles and obesity: a latent profile analysis of 24-h time-use composition among Danish workers.

BACKGROUND/OBJECTIVES: An element of obesity prevention is increasing total physical activity energy expenditure. However, this approach does not incorporate the balance of various movement behaviors-physical activity, sedentary behaviors and sleep-across domains of the day. We aimed to identify time-use profiles over work and leisure, termed 'movement behavior profiles' and to investigate their association with obesity. SUBJECTS/METHODS: Eight-hundred-and-seven workers completed (a) thigh accelerometry and diaries to determine their 24-h composition of behaviors (sedentary and standing, light physical activity and moderate-to-vigorous physical activity at work and leisure, and time in bed) and (b) obesity measurements. Movement behavior profiles were determined using latent profile analyses of isometric log-ratios of the 24-h composition, and labeled according to animal movement behavior traits. Linear models were applied to determine the association between profiles and obesity. RESULTS: Four profiles were identified, labeled as "Chimpanzees" (n = 226), "Lions" (n = 179), "Ants" (n = 244), and "Koalas" (n = 158). "Chimpanzees" work time was evenly distributed between behaviors while their leisure time was predominantly active. Compared to Chimpanzees, "Lions" were more active at work and sedentary during leisure and spent more time in bed; "Ants" were more active at work and during leisure; "Koalas" were more sedentary at work and leisure and spent similar time in bed. With "Chimpanzees" as reference, "Lions" had least favorable obesity indicators: +2.0 (95% confidence interval [CI] 0.6, 3.4) %body fat, +4.3 cm (1.4, 7.3) waist circumference and +1.0 (2.0, 0.0) Body Mass Index (BMI), followed by "Koalas" +2.0 (0.4, 3.7) %body fat, +3.1 cm (0.1, 6.0) waist circumference, and +0.8 (-0.30, 1.94) BMI. No significant differences were found between "Chimpanzees" and "Ants". CONCLUSIONS: Movement behavior profiles across work and leisure time-use compositions are associated with obesity. Achieving adequate balance between work and leisure movement behaviors should be further investigated as a potential obesity prevention strategy.

The physical activity paradox revisited: a prospective study on compositional accelerometer data and long-term sickness absence.

BACKGROUND: The 'physical activity paradox' advocates that leisure physical activity (PA) promotes health while high occupational PA impairs health. However, this paradox can be explained by methodological limitations of the previous studies-self-reported PA measures, insufficient adjustment for socioeconomic confounding or not addressing the compositional nature of PA. Therefore, this study investigated if we still observe the PA paradox in relation to long-term sick absence (LTSA) after adjusting for the abovementioned limitations. METHODS: Time spent on moderate-to-vigorous physical activity (MVPA) and remaining physical behaviors (sedentary behavior, standing, light PA and time in bed) at work and in leisure was measured for 929 workers using thigh accelerometry and expressed as isometric log-ratios (ilrs). LTSA was register-based first event of ≥6 consecutive weeks of sickness absence during 4-year follow-up. The association between ilrs and LTSA was analyzed using a Cox proportional hazards model adjusted for remaining physical behaviors and potential confounders, then separately adjusting for and stratifying by education and type of work. RESULTS: During the follow-up, 21% of the workers experienced LTSA. In leisure, more relative MVPA time was negatively associated with LTSA (20% lower risk with 20 min more MVPA, p = 0.02). At work, more relative MVPA time was positively associated with LTSA (15% higher risk with 20 min more MVPA, p = 0.02). Results remained unchanged when further adjusted for or stratified by education and type of work. CONCLUSION: These findings provide further support to the 'PA paradox'.

Are occupational physical activities tailored to the age of cleaners and manufacturing workers?

PURPOSE: An ageing population will necessitate people to work for longer. High occupational physical activities (OPA) are a well-documented barrier to sustainable employment. Blue-collar workers are at high risk for early exit from the labour market, which may be prevented by improved tailoring of OPA to the capacities of ageing workers. However, little is known about the current approaches used in blue collar workplaces. This study investigated age and OPA using objective field measurements in the cleaning and manufacturing sector. METHODS: Associations were examined between age and percentage of working time of three OPA: total time on feet, standing still and walking, among 615 cleaners and manufacturing workers from the Danish Physical Activity cohort with Objective measurements (DPhacto). OPA were measured over 3-4 days with accelerometers. Regression modeling was used to investigate the relationship between age and the respective OPA stratified by the two sectors after adjustment for potential confounders. RESULTS: No tendency for negative associations between age and OPA were found for either sector. To the contrary, a positive association between age and high levels of time on feet was found for male manufacturing workers (OR 1.05; 95% CI 1.02-1.08 per year). CONCLUSION: Using objective measurements of OPA, this study found that OPA are not tailored to the age of workers. To the contrary, some older workers are more likely to have higher OPA. A need exists for further investigation and development of guidelines to support job design that will enable older workers to remain employed.

The association between occupational standing and sedentary leisure time over consecutive workdays among blue-collar workers in manual jobs.

PURPOSE: Blue-collar workers spend much leisure time sedentary, which is associated with numerous health impairments. The extensive sedentary leisure time among blue-collar workers could be caused by fatigue from physically demanding work, like stationary standing. Occupational stationary standing is prevalent in many blue-collar jobs and has been shown to induce fatigue. The objective of this study was to investigate the association between occupational standing and sedentary leisure time over several workdays among blue-collar workers. METHODS: This study used data from 925 workers from Danish workplaces within cleaning, transportation, manufacturing, construction, road maintenance, garbage disposal, and health service. Eligible workers wore accelerometers for 2-5 consecutive workdays. A linear regression was used to investigate the association between percent of work time spent standing and leisure time spent sedentary. A multilevel growth model was used to assess the association between standing during work and sedentary leisure time over consecutive workdays. RESULTS: We found no association between percent of work hours spent standing and percent of leisure time spent sedentary (coef. = 0.01, p = 0.84). The results showed an increase in the workers' sedentary leisure time over a week (coef. = 0.70, p < 0.01). However, this increase was not associated with consecutive workdays exposed to occupational standing (coef. = 0.02, p = 0.42). CONCLUSION: In this study, we found no support of a positive association between occupational standing and sedentary leisure time. This lack of association could be attributable to a low variation in sedentary leisure time or the chosen definition and measurement of occupational standing.

The joint association of musculoskeletal pain and domains of physical activity with sleep problems: cross-sectional data from the DPhacto study, Denmark.

PURPOSE: To investigate if occupational physical activity (OPA) and leisure-time physical activity (LTPA) influence the association between musculoskeletal pain and sleep problems. METHODS: Cross-sectional study includes 678 workers in the Danish PHysical ACTivity cohort with Objective measurements (DPhacto). Musculoskeletal pain was assessed by questionnaires, while OPA and LTPA were measured with accelerometers for up to 6 consecutive days. We used logistic regression to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for self-reported insomnia symptoms and non-restorative sleep. RESULTS: Analyses of the joint association of musculoskeletal pain and OPA showed that workers with high pain and high OPA had ORs of 5.80 (95% CI 2.64-12.67) for insomnia symptoms and 2.50 (95% CI 1.37-4.57) for non-restorative sleep, compared to those with low pain and low OPA, whereas workers with high pain and low OPA had ORs of 4.67 (95% CI 2.17-10.07) for insomnia symptoms, and 2.67 (95% CI 1.46-4.89) for non-restorative sleep, respectively. Furthermore, workers with high pain and high LTPA had ORs of 4.23 (95% CI 2.16-8.32) for insomnia symptoms and 1.95 (95% CI 1.09-3.48) for non-restorative sleep, compared to those with low pain and low LTPA, whereas workers with high pain and low LTPA had ORs of 3.34 (95% CI 1.66-6.70) for insomnia symptoms and 2.14 (95% CI 1.21-3.80) for non-restorative sleep, respectively. CONCLUSIONS: Workers with high musculoskeletal pain who also conducted high levels of OPA or LTPA reported higher prevalence of insomnia symptoms.

Technically measured compositional physical work demands and prospective register-based sickness absence (PODESA): a study protocol.

BACKGROUND: Various physical work demands are shown to be associated with sickness absence. However, these studies have: (a) predominantly used self-reported data on physical work demands that have been shown to be inaccurate compared with technical measurements, (b) principally focused on various physical work demands in 'isolation', i.e. ignoring their co-dependency - compositional nature -, and (c) mainly used register data on long-term sickness absence. The present article describes the protocol of a study with the objective of investigating the association between technically measured compositional data on physical work demands and prospective long- and short-term register-based data on sickness absence. METHODS: 'The technically measured compositional Physical wOrk DEmands and prospective association with register-based Sickness Absence study (PODESA)' comprises data from two Danish cohorts (NOMAD and DPhacto) primarily on blue-collar workers. In the PODESA cohort, data on 1108 workers were collected at baseline (between 2011 and 2014). The cohort data comprise, e.g., self-reported information on descriptives, lifestyle, workday, and health, as well as accelerometer-based measurements of physical work demands (physical activity, movements, and postures). These baseline measurements are linked with prospective register-based data on sickness absence for up to four years after baseline. The prospective association between physical work demands and sickness absence will be analysed using a Compositional Data Analysis approach. DISCUSSION: PODESA provides a unique possibility of unravelling which combinations of physical work demands are associated with prospective sickness absence. PODESA employs technically measured information on physical work demands (taking into account the compositionality of physical work demand data) and prospective sickness absence data. The findings from PODESA can be used to develop strengthened preventive interventions for sickness absence. Results are expected in 2019-2021.

A comparison of standard and compositional data analysis in studies addressing group differences in sedentary behavior and physical activity.

BACKGROUND: Data on time spent in physical activity, sedentary behavior and sleep during a day is compositional in nature, i.e. they add up to a constant value. Compositional data have fundamentally different properties from unconstrained data in real space, and require other analytical procedures, referred to as compositional data analysis (CoDA). Most physical activity and sedentary behavior studies, however, still apply analytical procedures adapted to data in real space, which can lead to misleading results. The present study describes a comparison of time spent sedentary and in physical activity between age groups and sexes, and investigates the extent to which results obtained by CoDA differ from those obtained using standard analytical procedures. METHODS: Time spent sedentary, standing, and in physical activity (walking/running/stair climbing/cycling) during work and leisure was determined for 1-4 days among 677 blue-collar workers using accelerometry. Differences between sexes and age groups were tested using MANOVA, using both a standard and a CoDA approach based on isometric log-ratio transformed data. RESULTS: When determining differences between sexes for different activities time at work, the effect size using standard analysis (η2 = 0.045, p < 0.001) was 15% smaller than that obtained with CoDA (η2 = 0.052, p < 0.001), although both approaches suggested a statistically significant difference. When determining corresponding differences between age groups, CoDA resulted in a 60% larger, and significant, effect size (η2 = 0.012, p = 0.02) than that obtained with the standard approach (η2 = 0.008, p = 0.07). During leisure, results based on standard (age; η2 = 0.007, p = 0.09; sex; η2 = 0.052, p < 0.001) and CoDA (age; η2 = 0.007, p = 0.09; sex; η2 = 0.051, p < 0.001) analyses were similar. CONCLUSION: Results and, hence, inferences concerning age and sex-based differences in time spent sedentary and in physical activity at work differed between CoDA and standard analysis. We encourage researchers to use CoDA in similar studies, to adequately account for the compositional nature of data on physical activity and sedentary behavior.

The role of managers in addressing employees with musculoskeletal pain: a mixed methods study.

PURPOSE: This study investigates management awareness of employee musculoskeletal pain and conditions that shape managers' handling of employees with pain. METHODS: We used a mixed methods design including data from a questionnaire survey and focus group sessions. All employees and managers from seven nursing homes were invited to participate in the questionnaire survey and 327 employees (81%) and 31 managers (82%) responded. Employees were asked about their worst pain intensity the past month and managers were asked to estimate the percentage of their employees who had experienced pain. Thirty-eight managers (93%) participated in focus group sessions addressing the culture for handling pain at the workplace. A multiple case study approach allowed for an integrated interpretation of the empirical findings. RESULTS: Results indicate limited manager awareness of employee pain. We identified four conditions that shape managers' handling of employees with pain: (1) Employee handling of-and communication about-pain, (2) the collegial culture for handling pain, (3) managers' perception of their role towards employees with pain and (4) procedures and informal approaches for handling employees with pain. Across these conditions various degrees of openness characterized the nursing homes. CONCLUSIONS: The degree of openness towards communicating about-and handling pain-in the organization (individual, collegial and managerial levels) influences how managers handle employees with pain. Awareness about employee health is a prerequisite for management to initiate relevant action towards supporting employees. Future workplace initiatives are likely to benefit from addressing openness in the organization to increase awareness and support employees with pain.

A multi-faceted workplace intervention targeting low back pain was effective for physical work demands and maladaptive pain behaviours, but not for work ability and sickness absence: Stepped wedge cluster randomised trial.

AIMS: The aims of this study were to test whether a multi-faceted intervention effective for low back pain was effective for physical capacity, work demands, maladaptive pain behaviours, work ability and sickness absence due to low back pain. METHODS: A stepped wedge cluster randomised, controlled trial with 594 nurses' aides was conducted. The intervention lasted 12 weeks and consisted of physical training (12 sessions), cognitive behavioural training (two sessions) and participatory ergonomics (five sessions). Occupational lifting, fear avoidance, physical exertion, muscle strength, support from management, work ability and sickness absence due to low back pain were measured every 3 months. Before and after the intervention we measured physical capacity, kinesiophobia and need for recovery. Linear mixed models adjusted for baseline values of the outcome were used to estimate the effect. RESULTS: Significant reduction in occupational lifting (-0.35 (95% confidence interval -0.61 to -0.08)), and improvement in two measures of fear avoidance ((-0.75 (95% confidence interval -1.05 to -0.45) and -0.45 (95% confidence interval -0.80 to -0.11)) were found for the intervention group compared to the control. There were no significant effects on physical exertion, muscle strength, support from management, work ability or sickness absence due to low back pain. After the intervention, significant increased physical capacity and improvements in kinesiophobia were found, but no change in need for recovery. CONCLUSIONS THE INTERVENTION WAS SIGNIFICANTLY EFFECTIVE FOR PHYSICAL WORK DEMANDS AND MALADAPTIVE PAIN BEHAVIOURS, BUT NOT FOR WORK ABILITY AND SICKNESS ABSENCE DUE TO LOW BACK PAIN TO IMPROVE WORK ABILITY OR REDUCE SICKNESS ABSENCE DUE TO LOW BACK PAIN MORE SPECIFIC INTERVENTIONS SHOULD PROBABLY BE DEVELOPED.

Waste Workers' Exposure to Airborne Fungal and Bacterial Species in the Truck Cab and During Waste Collection.

A large number of people work with garbage collection, and exposure to microorganisms is considered an occupational health problem. However, knowledge on microbial exposure at species level is limited. The aim of the study was to achieve knowledge on waste collectors' exposure to airborne inhalable fungal and bacterial species during waste collection with focus on the transport of airborne microorganisms into the truck cab. Airborne microorganisms were collected with samplers mounted in the truck cab, on the workers' clothes, and outdoors. Fungal and bacterial species were quantified and identified. The study showed that the workers were exposed to between 112 and 4.8×10(4) bacteria m(-3) air and 326 and 4.6×10(4) fungi m(-3) air. The personal exposures to bacteria and fungi were significantly higher than the concentrations measured in the truck cabs and in the outdoor references. On average, the fungal and bacterial concentrations in truck cabs were 111 and 7.7 times higher than outdoor reference measurements. In total, 23 fungal and 38 bacterial species were found and identified. Most fungal species belonged to the genus Penicillium and in total 11 Penicillium species were found. Identical fungal species were often found both in a personal sample and in the same person's truck cab, but concentrations were on average 27 times higher in personal samples. Concentrations of fungal and bacterial species found only in the personal samples were lower than concentrations of species also found in truck cabs. Skin-related bacteria constituted a large fraction of bacterial isolates found in personal and truck cab samples. In total, six Staphylococcus species were found. In outdoor samples, no skin-related bacteria were found. On average, concentrations of bacterial species found both in the truck cab and personal samples were 77 times higher in personal samples than in truck cab samples. In conclusion, high concentrations of fungi were found in truck cabs, but the highest concentrations were found in personal samples; fungal and bacterial species found in high concentrations in personal samples were also found in truck cabs, but in lower concentrations indicating that both fungi and bacteria are transported by the workers into the truck cab, and are subsequently aerosolized in the truck cab.

Do working environment interventions reach shift workers?

PURPOSE: Shift workers are exposed to more physical and psychosocial stressors in the working environment as compared to day workers. Despite the need for targeted prevention, it is likely that workplace interventions less frequently reach shift workers. The aim was therefore to investigate whether the reach of workplace interventions varied between shift workers and day workers and whether such differences could be explained by the quality of leadership exhibited at different times of the day. METHODS: We used questionnaire data from 5361 female care workers in the Danish eldercare sector. The questions concerned usual working hours, quality of leadership, and self-reported implementation of workplace activities aimed at stress reduction, reorganization of the working hours, and participation in improvements of working procedures or qualifications. RESULTS: Compared with day workers, shift workers were less likely to be reached by workplace interventions. For example, night workers less frequently reported that they had got more flexibility (OR 0.5; 95 % CI 0.3-0.7) or that they had participated in improvements of the working procedures (OR 0.6; 95 % CI 0.5-0.8). Quality of leadership to some extent explained the lack of reach of interventions especially among fixed evening workers. CONCLUSIONS: In the light of the evidence of shift workers' stressful working conditions, we suggest that future studies focus on the generalizability of results of the present study and on how to reach this group and meet their needs when designing and implementing workplace interventions.

Temporal patterns of sitting at work are associated with neck-shoulder pain in blue-collar workers: a cross-sectional analysis of accelerometer data in the DPHACTO study.

BACKGROUND: Our aim was to examine the extent to which temporal patterns of sitting during occupational work and during leisure-time, assessed using accelerometry, are associated with intense neck-shoulder pain (NSP) in blue-collar workers. METHODS: The population consisted of 659 Danish blue-collar workers. Accelerometers were attached to the thigh, hip, trunk and upper dominant arm to measure sitting time and physical activity across four consecutive days. Temporal sitting patterns were expressed separately for work and leisure by the proportion of total time spent sitting in brief bursts (0-5 min), moderate (>5-20 min) and prolonged (>20 min) periods. The peak NSP intensity during the previous 3 months was assessed using a numerical rating scale (range 0-10) and dichotomized into a lower (≤4) and higher (>4) NSP score. Logistic regression analyses with multiple adjustments for individual and occupational factors were performed to determine the association between brief, moderate and prolonged sitting periods, and NSP intensity. RESULTS: Time in brief bursts of occupational sitting was negatively associated with NSP intensity (adjusted OR 0.68, 95 % CI 0.48-0.98), while time in moderate periods of occupational sitting showed a positive association with NSP (adjusted OR 1.32, 95 % CI 1.04-1.69). Time in prolonged periods of occupational sitting was not associated with NSP (adjusted OR 0.78, 95 % CI 0.78-1.09). We found no significant association between brief, moderate or prolonged sitting periods during leisure, and NSP. CONCLUSION: Our findings indicate that the association between occupational sitting time and intense NSP among blue-collar workers is sensitive to the temporal pattern of sitting.

Are temporal patterns of sitting associated with obesity among blue-collar workers? A cross sectional study using accelerometers.

BACKGROUND: Little is known about associations of temporal patterns of sitting (i.e., distribution of sitting across time) with obesity. We aimed investigating the association between temporal patterns of sitting (long, moderate and brief uninterrupted bouts) and obesity indicators (body mass index (BMI), waist circumference and fat percentage), independently from moderate-vigorous physical activity (MVPA) and total sitting time among blue-collar workers. METHODS: Workers (n = 205) wore Actigraph GT3X+ accelerometers on the thigh and trunk for 1-4 working days. Using the validated Acti4 software, the total sitting time and time spent sitting in brief (≤5 mins), moderate (>5 and ≤30 mins), and long (>30mins) bouts on working days were determined for the whole day, and for leisure and work separately. BMI (kg/m(2)), waist circumference (cm) and fat percentage were objectively measured. RESULTS: Results of linear regression analysis adjusted for multiple confounders indicated that brief bouts of sitting was negatively associated with obesity for the whole day (BMI, P < 0.01; fat percentage, P < 0.01; waist circumference, P < 0.01) and work (BMI, P < 0.01; fat percentage, P < 0.01; waist circumference, P < 0.01), but not for leisure. Sitting time in long bouts was positively associated with obesity indicators for the whole day (waist circumference, P = 0.05) and work (waist circumference, P = 0.01; BMI, P = 0.04), but not leisure. CONCLUSIONS: For the whole day as well as for work, brief bouts and long bouts of sitting showed opposite associations with obesity even after adjusting for MVPA and total sitting time, while sitting during leisure did not show these associations. Thus, the temporal distribution of sitting seems to influence the relationship between sitting and obesity.

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.

Health promotion in primary and secondary schools in Denmark: time trends and associations with schools' and students' characteristics.

BACKGROUND: Schools are important arenas for interventions among children as health promoting initiatives in childhood is expected to have substantial influence on health and well-being in adulthood. In countries with compulsory school attention, all children could potentially benefit from health promotion at the school level regardless of socioeconomic status or other background factors. The first aim was to elucidate time trends in the number and types of school health promoting activities by describing the number and type of health promoting activities in primary and secondary schools in Denmark. The second aim was to investigate which characteristics of schools and students that are associated with participation in many (≥3) versus few (0-2) health promoting activities during the preceding 2-3 years. METHODS: We used cross-sectional data from the 2006- and 2010-survey of the Health Behaviour in School-aged Children study. The headmasters answered questions about the school's participation in health promoting activities and about school size, proportion of ethnic minorities, school facilities available for health promoting activities, competing problems and resources at the school and in the neighborhood. Students provided information about their health-related behavior and exposure to bullying which was aggregated to the school level. A total of 74 schools were available for analyses in 2006 and 69 in 2010. We used chi-square test, t-test, and binary logistic regression to analyze time trends and differences between schools engaging in many versus few health promoting activities. RESULTS: The percentage of schools participating in ≥3 health promoting activities was 63% in 2006 and 61% in 2010. Also the mean number of health promoting activities was similar (3.14 vs. 3.07). The activities most frequently targeted physical activity (73% and 85%) and bullying (78% and 67%). Schools' participation in anti-smoking activities was significantly higher in 2006 compared with 2010 (46% vs. 29%). None of the investigated variables were associated with schools' participation in health promoting activities. CONCLUSION: In a Danish context, schools' participation in health promotion was rather stable from 2006 to 2010 and unrelated to the measured characteristics of the schools and their students.

Does rare use of assistive devices during patient handling increase the risk of low back pain? A prospective cohort study among female healthcare workers.

PURPOSE: To investigate whether rare use of assistive devices during patient handling increases the respective risk for infrequent and frequent low back pain (LBP) among female healthcare workers reporting to be free of LBP at baseline. METHOD: Female healthcare workers replied to questionnaires about use of assistive devices during patient handling activities (rarely, occasionally and often) and LBP in both 2005 and 2006. Among those reporting to be free of LBP (0 days the past 12 months) in 2005 (n = 1,478), the multi-adjusted odds ratio for developing infrequent LBP (1-30 days the past 12 months) and frequent LBP (>30 days the past 12 months) in 2006 depending on use of assistive devices was prospectively investigated. RESULTS: The multi-adjusted odds ratio for developing infrequent LBP was 1.21 (95 % CI 0.90-1.62) for those occasionally using assistive devices, and 1.78 (95 % CI 1.19-2.66) for those rarely using assistive devices, referencing healthcare workers often using assistive devices during patient handling (p < 0.01 for trend). No associations between use of assistive devices during patient handling and risk of frequent LBP were found. CONCLUSION: The study indicates that rare use of assistive devices can increase the risk for developing infrequent LBP in female healthcare workers reporting to be free from LBP at baseline.

Does workplace health promotion in Denmark reach relevant target groups?

The aim of the current study was to investigate whether Workplace Health Promotion (WHP) is available for workers with poor health status (overweight, musculoskeletal disorders, sickness absence and poor self-rated health) or health behaviour (smoking, poor diet and sedentarism) and whether they participate in WHP. In total, 9835 workers responded to questions regarding availability to 6 different types of WHP through The Danish Work Environment Cohort Study in 2010. Logistic regression analyses adjusted for age, gender and industry were performed to calculate odds ratios for availability and participation of WHP among groups with different health behaviours and health status. In general, poor health behaviours were associated with reduced availability of and participation in WHP. In contrast, poor health status was generally associated with higher availability of WHP and increased participation. However, poor self-rated health was associated with lower availability of several types of WHP and reduced participation. In general, workers with health challenges that are visible to others had WHP available, whereas workers with less visible health challenges had WHP less frequently available. Health challenges visible to others were associated with higher participation in WHP, whereas poor health behaviour and reduced self-rated health were associated with reduced participation in WHP programmes.

Organizing workplace health literacy to reduce musculoskeletal pain and consequences.

BACKGROUND: Despite numerous initiatives to improve the working environment for nursing aides, musculoskeletal disorders (pain) is still a considerable problem because of the prevalence, and pervasive consequences on the individual, the workplace and the society. Discrepancies between effort and effect of workplace health initiatives might be due to the fact that pain and the consequences of pain are affected by various individual, interpersonal and organizational factors in a complex interaction. Recent health literacy models pursue an integrated approach to understanding health behavior and have been suggested as a suitable framework for addressing individual, organizational and interpersonal factors concomitantly. Therefore, the aim of the trial is to examine the effectiveness of an intervention to improve health literacy (building knowledge, competences and structures for communication and action) at both the organizational and individual level and reduce pain among nursing aides. METHODS/DESIGN: The intervention consists of 2 steps: 1) Courses at the workplace for employees and management in order to organize a joint fundament of knowledge and understanding, and a platform for communication and action about pain prevention in the organization. 2) Organizing a fixed 3-weekly structured dialogue between each employee and her/his supervisor, with particular focus on developing specific plans to prevent and reduce pain and its consequences. This enables the workplace to generate knowledge about employee resources and health challenges and to act and convey this knowledge into initiatives at the workplace. DISCUSSION: Previous studies to improve health literacy have primarily targeted patients or specific deprived groups in health care or community settings. Recently the idea of the workplace as an arena for improving health literacy has developed emphasizing the organizational responsibility in facilitating and supporting that employees obtain basic knowledge and information needed to understand and take action on individual and occupational health concerns. The literature about workplace health literacy is very limited but points at the importance of educating employees to be able to access, appraise and apply health information and of organizing the infrastructure and communication in the organization. This study suggests a concrete operationalization of health literacy in a workplace setting. Results are expected published in 2016.