A Decision Aid to Support Vocational Rehabilitation Professionals Offering Tailored Care to Benefit Recipients with a Long-Term Work Disability: A Feasibility Study.

PURPOSE: This feasibility study focusses on the implementation and use of a decision aid, which supports vocational rehabilitation (VR) professionals in helping clients with a disability pension return to work in practice. The decision aid shows an overview of the clients' return to work barriers and suggests suitable VR interventions based on these barriers. METHODS: The study population consisted of VR professionals working at the Dutch Social Security Institute and their clients receiving a (partial) work disability pension. The feasibility was measured with concepts of the Linnan and Steckler framework and the attitude, social norm and self-efficacy model. Data were collected using questionnaires, checklists and qualitative interviews. RESULTS: Ten professionals participated in this study. Fifty-four clients were asked to fill in the questionnaire of the decision aid and 32 clients received VR care based on the decision aid. In general, VR professionals and clients were satisfied with the decision aid and perceived a few barriers for using the decision aid. CONCLUSIONS: This study showed that it is feasible to implement and use the decision aid. To improve the implementation of this decision aid, it should be implemented in digital systems used by professionals to improve efficiency of working with the decision aid.

Elements of Return-to-Work Interventions for Workers on Long-Term Sick Leave: A Systematic Literature Review.

PURPOSE: The aim of this systematic review is to identify vocational rehabilitation (VR) interventions that are effective to enhance return-to-work (RTW) for people on long-term sick leave (> 90 days) and to identify main elements of these interventions. METHODS: Six electronic databases were searched for peer-reviewed studies published up to February 2022. Each article was screened independently by two different reviewers. Thereafter, one author performed the data-extraction which was checked by another author. The EPHPP quality assessment tool was used to appraise the methodological quality of the studies. RESULTS: 11.837 articles were identified. 21 articles were included in the review, which described 25 interventions. Results showed that ten interventions were more effective than usual care on RTW. Two interventions had mixed results. The effective interventions varied widely in content, but were often more extensive than usual care. Common elements of the effective interventions were: coaching, counseling and motivational interviewing, planning return to work, placing the worker in work or teaching practical skills and advising at the workplace. However, these elements were also common in interventions that were not effective on RTW compared to usual care and can therefore not explain why certain interventions are effective and others are not. CONCLUSION: The effective interventions included in this study were often quite extensive and aimed at multiple phases of the RTW-process of the worker. In the future, researchers need to describe the population and the content of the investigated interventions more elaborate to be able to better compare VR interventions and determine what elements make interventions effective.

Work and health during the COVID-19 crisis among Dutch workers and jobseekers with (partial) work disabilities: a mixed methods study.

BACKGROUND: The consequences of restrictive measures during the COVID-19 outbreak have potentially been enormous, especially for those in a vulnerable position in the labour market. This study aims to describe the impact of the COVID-19 crisis on work status, working conditions and health among people with (partial) work disabilities-with and in search of work-during the COVID-19 pandemic in the Netherlands. METHODS: A mixed methods design was used, combining a cross-sectional online survey and ten semi-structured interviews with people with a (partial) work disability. The quantitative data included responses to job-related questions, self-reported health, and demographics. The qualitative data consisted of participants' perceptions about work, vocational rehabilitation, and health. We used descriptive statistics to summarize the responses, conducted logistic and linear regression and integrated our qualitative findings with the quantitative findings, aiming at complementarity. RESULTS: Five hundred and eighty-four participants (response rate 30.2%) completed the online survey. The majority of participants experienced no change in work status: 39 percent remained employed, 45 percent remained unemployed, six percent of respondents lost their job, and ten percent became employed during the COVID-19 crisis. In general, the results showed a deterioration in self-rated health during the COVID-19 outbreak, both for participants at work and in search of work. Participants who lost their job during the COVID-19 crisis reported the highest deterioration in self-rated health. Interview findings revealed that loneliness and social isolation were persistent during the COVID-19 crisis, especially among those in search of work. Additionally, employed participants identified a safe work environment and the possibility to work at the office as important factors for overall health. CONCLUSIONS: The vast majority of study participants (84.2%) experienced no change in work status during the COVID-19 crisis. Nonetheless, people at work and in search of work encountered barriers to maintaining or (re)gaining employment. People with a (partial) work disability who lost their job during the crisis appeared to be most affected in terms of health. Employment and health protections could be strengthened for persons with (partial) work disabilities in order to build resilience in times of crisis.

Experiences and needs of welfare benefit recipients regarding their welfare-to-work services and case workers.

BACKGROUND: This study aimed to explore the experiences and needs of (ex-)welfare benefit recipients from a large urban municipality in the Netherlands regarding their welfare-to-work services and their case workers. METHODS: Quantitative data from a client satisfaction survey that was filled out by 213 people (response rate 11%) who received welfare-to-work services was combined with results from four group interviews with a total of 15 people receiving welfare-to-work services. Verbatim transcripts from the interviews were analysed using inductive thematic analysis. RESULTS: The survey results showed that most clients were reasonably satisfied with the welfare-to-work services they received. Four main themes emerged from the interviews: (1) experiences and needs related to the interactions between case workers and benefit recipients; (2) the need for tailored services; (3) the complicating role of the system the case workers operate within; and (4) the existence of differences between case workers regarding how strict they followed the rules and to what extent they connected with their clients on a personal level. CONCLUSIONS: Our findings show that clients were reasonably satisfied with the welfare-to-work services provided by their municipality but that there is still room for improvement. Case workers should have good social skills to build a trusting relationship with the client, welfare-to-work services should be tailored to the individual, and clear concise information should be given to welfare benefit recipients, especially with regard to what benefit recipients can expect of the municipality and the case workers, given their dual role in supporting (re-)integration to work and monitoring benefit eligibility.

Return to work factors and vocational rehabilitation interventions for long-term, partially disabled workers: a modified Delphi study among vocational rehabilitation professionals.

BACKGROUND: Long-term disability has a great impact on both society and workers with disabilities. Little is known about the barriers which prohibit workers with long-term disabilities from returning to work and which interventions are best suited to counteract these barriers. The main purpose of this study was to obtain consensus among professionals on important return to work (RTW) factors and effective vocational rehabilitation (VR) interventions for long-term (> 2 years), partially disabled workers. Our three research questions were: (1) which factors are associated with RTW for long-term disabled workers?; (2) which factors associated with RTW can be targeted by VR interventions?; and (3) which VR interventions are the most effective to target these factors? METHODS: A modified Delphi Study was conducted using a panel of 22 labour experts, caseworkers, and insurance physicians. The study consisted of several rounds of questionnaires and one online meeting. RESULTS: The multidisciplinary panel reached consensus that 58 out of 67 factors were important for RTW and that 35 of these factors could be targeted using VR interventions. In five rounds, the expert panel reached consensus that 11 out of 22 VR interventions were effective for at least one of the eight most important RTW factors. CONCLUSIONS: Consensus was reached among the expert panel that many factors that are important for the RTW of short-term disabled workers are also important for the RTW of long-term partially disabled workers and that a substantial number of these factors could effectively be targeted using VR interventions. The results of this study will be used to develop a decision aid that supports vocational rehabilitation professionals in profiling clients and in choosing suitable VR interventions.

Barriers and facilitators influencing the implementation of the occupational health intervention 'Dynamic Work': a qualitative study.

BACKGROUND: Sedentary behavior is associated with an increased risk of morbidity and mortality. To reduce occupational sitting time of office workers, the multi-component intervention 'Dynamic Work' was implemented in a Dutch insurance company. Although the results showed no significant reductions in sitting time, associations were found between higher levels of implementation and reductions in sitting time. Building upon these findings, this qualitative study aimed to identify barriers and facilitators from an organizational perspective for the implementation of Dynamic Work. In addition, we explored differences in barriers and facilitators between departments with a low, middle and high level of implementation. METHODS: In total, eighteen semi-structured interviews were conducted with two Dynamic Work coordinators, three occupational physiotherapists who delivered the intervention, and thirteen department managers. All participants were purposively sampled. The data was coded in Atlas.ti and a thematic analysis was performed guided by The Integrated Checklist of Determinants (TICD). RESULTS: Implementation factors were related to the organization; working culture and financial support facilitated implementation. Factors related to the implementing department mainly hindered implementation, i.e. lack of information at start of the project, late delivery of Dynamic Work equipment, large group sizes, employee's workload and work tasks, and an ongoing reorganization. The facilitating role of managers was experienced as both enabling and hindering. The pre-existing familiarity of the occupational physiotherapists with the departments and alignment amongst the three implementers facilitated implementation. Yet, the non-obligatory nature of the intervention as well as limited availability and technical problems of equipment did not support implementation. CONCLUSIONS: Various barriers and facilitators influenced the implementation of the Dynamic Work intervention, where the key role of the department manager, late delivery of dynamic work equipment and groups sizes varied between low and high implementing departments. These results can contribute to developing and improving implementation strategies in order to increase the effectiveness of future occupational health interventions. TRIAL REGISTRATION: The study protocol was registered on April 14, 2017 in the ClinicalTrials.gov Protocol Registration and Results System under registration number NCT03115645 .

Proposal to extend the PROMIS® item bank v2.0 'Ability to Participate in Social Roles and Activities': item generation and content validity.

PURPOSE: Previous research indicated that the Patient-Reported Outcomes Measurement Information System (PROMIS®) item bank v2.0 'Ability to Participate in Social Roles and Activities' may miss subdomains of social participation. The purpose of this study was to generate items for these missing subdomains and to evaluate their content validity. METHODS: A three-step approach was followed: (1) Item generation for 16 International Classification of Functioning Disability and Health subdomains currently not covered by the item bank; (2) Evaluation of content validity of generated items through expert review (n = 20) and think-aloud interviews with a purposeful sample of people with and without (chronic) health conditions (n = 10), to assess item comprehensibility, relevance, and comprehensiveness; and 3) Item revision based on the results of step 2, in a consensus procedure. RESULTS: First, 48 items were generated. Second, overall, content experts indicated that the generated items were relevant. Furthermore, based on experts' responses, items were simplified and 'participation in social media' was identified as an important additional subdomain of social participation. Additionally, 'participating in various social roles simultaneously' was identified as a missing item. Based on the responses of the interviewed adults items were simplified. Third, in total 17 items, covering 17 subdomains, were proposed to be added to the original item bank. DISCUSSION: The relevance, comprehensibility and comprehensiveness of the 17 proposed items were supported. Whether the proposed extension of the item bank leads to better psychometric properties of the item bank should be tested in a large-scale field study.

How does occupational physical activity influence health? An umbrella review of 23 health outcomes across 158 observational studies.

OBJECTIVE: Physical activity (PA) has substantial benefits across a range of health outcomes. There is uncertainty about the PA-specific health effects, and in particular, the occupational domain. In this umbrella review, we synthesised available evidence on the associations between occupational PA (OPA) and health-related outcomes (including cancer, all-cause mortality and cardiovascular disease). This work informed the development of WHO's guidelines on PA and sedentary behaviour (2020). DESIGN: Umbrella review of systematic reviews. DATA SOURCE: We performed a literature search in PubMed, Web of Science, Embase, CINAHL and Sportdiscuss from database inception to 2 December 2019. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: We included systematic reviews if they contained a quantitative assessment of OPA and its relationship with at least one health-related outcome. RESULTS: We summarised the evidence of 17 reviews covering 23 unique health-related outcomes. We graded most evidence as low or very low, or moderate quality. We found health benefits for those engaging in high versus low OPA for multiple cancer outcomes (including colon and prostate), ischaemic stroke, coronary heart disease and mental health (ie, mental well-being and life satisfaction). High OPA was associated with unfavourable health outcomes for all-cause mortality in men, mental ill health (ie, depression and anxiety), osteoarthritis, and sleep quality and duration. CONCLUSIONS: We found favourable associations for most health-related outcomes with high OPA levels, but we also found some evidence for unfavourable associations due to high OPA levels. At this point, there is a need for better quality evidence to provide a unequivocal statement on the health effects of OPA.

Predicting Long-Term Sickness Absence and Identifying Subgroups Among Individuals Without an Employment Contract.

Purpose Today, decreasing numbers of workers in Europe are employed in standard employment relationships. Temporary contracts and job insecurity have become more common. This study among workers without an employment contract aimed to (i) predict risk of long-term sickness absence and (ii) identify distinct subgroups of sick-listed workers. Methods 437 individuals without an employment contract who were granted a sickness absence benefit for at least two weeks were followed for 1 year. We used registration data and self-reported questionnaires on sociodemographics, work-related, health-related and psychosocial factors. Both were retrieved from the databases of the Dutch Social Security Institute and measured at the time of entry into the benefit. We used logistic regression analysis to identify individuals at risk of long-term sickness absence. Latent class analysis was used to identify homogenous subgroups of individuals. Results Almost one-third of the study population (n = 133; 30%) was still at sickness absence at 1-year follow-up. The final prediction model showed fair discrimination between individuals with and without long-term sickness absence (optimism adjusted AUC to correct for overfitting = 0.761). Four subgroups of individuals were identified based on predicted risk of long-term sickness absence, self-reported expectations about recovery and return to work, reason of sickness absence and coping skills. Conclusion The logistic regression model could be used to identify individuals at risk of long-term sickness absence. Identification of risk groups can aid professionals to offer tailored return to work interventions.

Associations of screen work with neck and upper extremity symptoms: a systematic review with meta-analysis.

OBJECTIVES: It has often been suggested that screen work (ie, work on desktop, laptop, notebook or tablet computers) is a risk factor for neck and upper extremity symptoms. However, an up-to-date overview and quantification of evidence are lacking. We aimed to systematically review the association of exposure to screen work with neck and upper extremity symptoms from prospective studies. METHODS: An electronic database search (PubMed, Embase, Cinahl and Scopus) for prospective studies on the association of exposure to screen work and musculoskeletal symptoms was conducted. Studies were synthesised regarding extracted data and risk of bias, and meta-analyses were conducted. RESULTS: After screening 3423 unique references, 19 articles from 12 studies (with 18 538 participants) were included for the current review, with the most recent exposure assessment reported in 2005. Studies described duration and input frequency of screen work (ie, computer, keyboard and mouse use, assessed using self-reports or software recordings) and musculoskeletal symptoms (ie, self-reported neck/shoulder and distal upper extremity symptoms and diagnosed carpal tunnel syndrome [CTS]). Although there was overall an increased occurrence of musculoskeletal symptoms with larger exposure to screen work (relative risk: 1.11 [1.03 1.19]), findings were rather inconsistent with weaker (and statistically non-significant) risks when screen work was assessed by software recording (1.05 [0.91 1.21]) compared to with self-report (1.14 [1.03 1.19]). CONCLUSIONS: We found an increased risk of musculoskeletal symptoms with screen work. However, the evidence is heterogeneous, and it is striking that it lacks information from contemporary screen work using laptop, notebook or tablet computers.

The Dynamic Work study: study protocol of a cluster randomized controlled trial of an occupational health intervention aimed at reducing sitting time in office workers.

BACKGROUND: Large volumes of sitting time have been associated with multiple health risks. To reduce sitting time of office workers working for a Dutch insurance company, the Dynamic Work intervention was developed. The primary objective of this paper is to describe the study protocol of the Dynamic Work study, which aims to evaluate if this multicomponent intervention is (cost-)effective in reducing total sitting time on the short-term (≈3 months) and longer-term (≈12 months) compared to usual practice. METHODS/DESIGN: This two-arm cluster randomized controlled trial will recruit 250 desk-based office workers working at different locations of an insurance company in the Netherlands. After baseline measurements, departments will be matched in pairs and each pair will be randomly assigned to the control or intervention condition. The multicomponent intervention contains organizational (i.e. face to face session with the head of the department), work environmental (i.e. the introduction of sit-stand desks and cycling workstations), and individual elements (i.e. counselling and activity/sitting tracker with a self-help program booklet). The counselling involves two group intervention sessions and four on-site department consultations with an occupational physiotherapist. Sitting time (primary outcome), upright time and step counts will be assessed objectively using the activPAL activity monitor at baseline, short-term (approximately 3 months) and longer-term (12 months). Other outcomes will include: self-reported lifestyle behaviours, anthropometrics, work-related outcomes (i.e. absenteeism, presenteeism, work performance, work-related stress), health-related outcomes (i.e. vitality, musculoskeletal symptoms, need for recovery, quality of life), and costs from both company and societal perspective. The study will include economic and process evaluations. DISCUSSION: This study will assess the longer-term (cost-) effectiveness of a multicomponent workplace intervention aimed at reducing sitting time in comparison with usual practice. Furthermore, the process evaluation will provide insights in factors associated with successful implementation of this intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT03115645 ; Registered 13 April 2017. Retrospectively registered.

Characteristics of individuals receiving disability benefits in the Netherlands and predictors of leaving the disability benefit scheme: a retrospective cohort study with five-year follow-up.

BACKGROUND: Today, work disability is one of the greatest social and labour market challenges for policy makers in most OECD countries, where on average, about 6% of the working-age population relies on disability benefits. Understanding of factors associated with long-term work disability may be helpful to identify groups of individuals at risk for disability benefit entitlement or continuing eligibility, and to develop effective interventions for these groups. The purpose of this study is to provide insight into the main diagnoses of workers who qualify for disability benefits and how these diagnoses differ in age, gender and education. Using a five-year follow-up, we examined the duration of disability benefits and how durations differ among individuals with various characteristics. METHODS: We performed a cohort study of 31,733 individuals receiving disability benefits from the Dutch Social Security Institute (SSI) with a five-year follow-up. Data were collected from SSI databases. Information about disorders was assessed by an insurance physician upon benefit application. These data were used to test for significant relationships among socio-demographics, main diagnoses and comorbidity, and disability benefit entitlement and continuing eligibility. RESULTS: Mental disorders were the most frequent diagnosis for individuals claiming work disability. Diagnoses differed among age groups and education categories. Mental disorders were the main diagnosis for work disability for younger and more highly educated individuals, and physical disorders (generally musculoskeletal, cardiovascular and cancer) were the main diagnosis for older and less educated individuals. In 82% of the claims, the duration of disability benefit was five years or more after approval. Outflow was lowest for individuals with (multiple) mental disorders and those with comorbidity of mental and physical disorders, and highest for individuals with (multiple) physical disorders. CONCLUSIONS: The main diagnosis for persons entitled to disability benefits was mental health problems, especially for young women. In a five-year follow-up, claim duration for disability benefits was long lasting for most claimants.

Do highly physically active workers die early? A systematic review with meta-analysis of data from 193 696 participants.

OBJECTIVE: Recent evidence suggests the existence of a physical activity paradox, with beneficial health outcomes associated with leisure time physical activity, but detrimental health outcomes for those engaging in high level occupational physical activity. This is the first quantitative systematic review of evidence regarding the association between occupational physical activity and all-cause mortality. DESIGN: Systematic review with meta-analysis. DATA SOURCE: A literature search was performed in electronic databases PubMed, Embase, CINAHL, PsycINFO and Cochrane. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: We screened for peer reviewed articles from prospective studies assessing the association of occupational physical activity with all-cause mortality. A meta-analysis assessed the association of high (compared with low) level occupational physical activity with all-cause mortality, estimating pooled hazard ratios (HR) (with 95% CI). RESULTS: 2490 unique articles were screened and 33 (from 26 studies) were included. Data from 17 studies (with 193 696 participants) were used in a meta-analysis, showing that men with high level occupational physical activity had an 18% increased risk of early mortality compared with those engaging in low level occupational physical activity (HR 1.18, 95% CI 1.05 to 1.34). No such association was observed among women, for whom instead a tendency for an inverse association was found (HR 0.90, 95% CI 0.80 to 1.01). CONCLUSIONS: The results of this review indicate detrimental health consequences associated with high level occupational physical activity in men, even when adjusting for relevant factors (such as leisure time physical activity). These findings suggest that research and physical activity guidelines may differentiate between occupational and leisure time physical activity.

'The End of Sitting' in a public space: observations of spontaneous visitors.

BACKGROUND: Sitting too much has been associated with negative health outcomes. 'The End of Sitting' is a newly developed office landscape that moves away from the traditional chair-desk setup. The landscape aims to reduce sitting time by offering a variety of (supported) standing positions. The aim of this study was to determine the usage of the landscape after being placed in the main entrance hall of the VU University in Amsterdam. METHODS: We observed the number of spontaneous visitors as well as the duration of visits, changes to another location within the landscape, and adopted postures. Using questionnaires reasons (not) to visit the landscape, perceived affordances of the landscape and associations with long-term use were determined. RESULTS: Observed numbers of visitors were relatively low and duration of visits were short, which seemed to indicate visitors were trying out the landscape. The majority of visitors were in an upright position, reflecting the designers' intentions. Visitors indicated that long-term use would be pleasant to them. CONCLUSION: 'The End of Sitting' landscape received positive reactions but number of visits were limited in the few months that it was placed in the university main entrance hall. The landscape might be better suited for designated working or study spaces, for which it was originally intended. It might also be worth to explore the landscapes suitability for short stay environments, such as waiting rooms.

Nonstandard working schedules and health: the systematic search for a comprehensive model.

BACKGROUND: Theoretical models on shift work fall short of describing relevant health-related pathways associated with the broader concept of nonstandard working schedules. Shift work models neither combine relevant working time characteristics applicable to nonstandard schedules nor include the role of rest periods and recovery in the development of health complaints. Therefore, this paper aimed to develop a comprehensive model on nonstandard working schedules to address these shortcomings. METHODS: A literature review was conducted using a systematic search and selection process. Two searches were performed: one associating the working time characteristics time-of-day and working time duration with health and one associating recovery after work with health. Data extracted from the models were used to develop a comprehensive model on nonstandard working schedules and health. RESULTS: For models on the working time characteristics, the search strategy yielded 3044 references, of which 26 met the inclusion criteria that contained 22 distinctive models. For models on recovery after work, the search strategy yielded 896 references, of which seven met the inclusion criteria containing seven distinctive models. Of the models on the working time characteristics, three combined time-of-day with working time duration, 18 were on time-of-day (i.e. shift work), and one was on working time duration. The model developed in the paper has a comprehensive approach to working hours and other work-related risk factors and proposes that they should be balanced by positive non-work factors to maintain health. Physiological processes leading to health complaints are circadian disruption, sleep deprivation, and activation that should be counterbalanced by (re-)entrainment, restorative sleep, and recovery, respectively, to maintain health. CONCLUSIONS: A comprehensive model on nonstandard working schedules and health was developed. The model proposes that work and non-work as well as their associated physiological processes need to be balanced to maintain good health. The model gives researchers a useful overview over the various risk factors and pathways associated with health that should be considered when studying any form of nonstandard working schedule.

Office workers with high effort-reward imbalance and overcommitment have greater decreases in heart rate variability over a 2-h working period.

PURPOSE: High levels of workplace psychosocial factors have been associated with adverse cardiovascular outcomes, possibly through the pathway of increasing autonomic arousal. The purpose of this study was to investigate whether the workplace psychosocial factors of effort-reward imbalance (ERI) and overcommitment were associated with greater decreases in heart rate variability (HRV) across a 2-h working period in a cohort of office workers performing their own work at their own workplaces. METHODS: Measurements of HRV in 5-min time epochs across a 2-h morning or afternoon working period, as well as self-reports of ERI and overcommitment, were collected for 91 office workers. RESULTS: There was a negative and significant (p < 0.01) ERI*time interaction for the standard deviation of the interval between normal heart beats (SDNN), the square root of the mean squared differences of successive normal heart beats (RMSSD), and the power in the high-frequency range of the heart rate signal (HF power), and a positive and significant ERI*time interaction for the ratio of power in the low-frequency range of the heart rate signal divided by the HF power (LF/HF ratio). There was a positive and significant overcommitment*time interaction for the LF/HF ratio (p < 0.01) in the morning, and a negative and significant overcommitment*time interaction for SDNN, RMSSD, and HF power (p < 0.01) in the afternoon. CONCLUSIONS: The results indicate that participants exposed to high levels of ERI and overcommitment exhibited a more adverse cardiovascular response (a greater decrease in HRV throughout the 2-h measurement period) compared to their colleagues with lower levels of these factors.

Neuroendocrine recovery after 2-week 12-h day and night shifts: an 11-day follow-up.

PURPOSE: The study aimed to investigate the course and duration of neuroendocrine recovery after 2-week 12-h day and night shift working periods and to study whether there were differences in recovery between the shift groups. METHODS: Twenty-nine male offshore employees working 2-week 12-h shift tours participated in the study; 15 participated after a day shift tour and 14 after a night shift tour. Salivary cortisol was assessed at awakening, 30 min after awakening, and before bedtime on the 1st, 4th, 7th, and 11th day of the free period, with a reference day prior to the offshore tour. Differences were tested using generalised estimating equations analysis. RESULTS: Compared to the reference day, night shift workers had a significantly flatter cortisol profile on the 1st day off, significantly lower cortisol concentrations at 30 min after awakening on day 4 and at awakening on day 7, and a significantly smaller decline to evening concentration on days 4 and 11. Compared to the reference day, day shift workers only showed a significantly lower cortisol concentration at awakening on the 1st day off. Compared to day workers, night shift workers had a flatter profile on the 1st day off and a lower cortisol concentration at awakening on the 4th day. CONCLUSIONS: Following 2-week 12-h night shift working periods, recovery was not fully complete up to day 11. Following 2-week 12-h day shift working periods, an indication of incomplete recovery was found on the 1st day off, with full recovery reached on day 4.

The influence of psychosocial work characteristics on the need for recovery from work: a prospective study among computer workers.

PURPOSE: To investigate the influence of high job demands, low job control, and high social support on need for recovery (NFR) among computer workers. METHODS: Data was obtained from a longitudinal cohort study, including 5 consecutive measurements, with an in-between period of 6 months. General estimating equations analyses were performed to assess the risk for high NFR 6 months later. Odds ratios (ORs) for high NFR were calculated for high job demands, low job control and low social support, separately. Likewise, ORs were calculated for combinations of job demands and job control, as well as for combinations of job demands, job control and social support. RESULTS: High job demands resulted in an increased risk for high NFR 6 months later, particularly in older workers. Low social support showed also an increased risk for future high NFR, but this was not the case for low job control. Furthermore, a combination of high job demands and low job control, as well as a combination of high job demands, low job control and low social support demonstrated an increased risk for future high NFR where older workers showed higher risks. CONCLUSION: This study demonstrated that adverse psychosocial work characteristics predicted future NFR among computer workers.

Prediction of trapezius muscle activity and shoulder, head, neck, and torso postures during computer use: results of a field study.

BACKGROUND: Due to difficulties in performing direct measurements as an exposure assessment technique, evidence supporting an association between physical exposures such as neck and shoulder muscle activities and postures and musculoskeletal disorders during computer use is limited. Alternative exposure assessment techniques are needed. METHODS: We predicted the median and range of amplitude (90th-10th percentiles) of trapezius muscle activity and the median and range of motion (90th-10th percentiles) of shoulder, head, neck, and torso postures based on two sets of parameters: the distribution of keyboard/mouse/idle activities only ("task-based" predictions), and a comprehensive set of task, questionnaire, workstation, and anthropometric parameters ("expanded model" predictions). We compared the task-based and expanded model predictions based on R2 values, root mean squared (RMS) errors, and relative RMS errors calculated compared to direct measurements. RESULTS: The expanded model predictions of the median and range of amplitude of trapezius muscle activity had consistently better R2 values (range 0.40-0.55 compared to 0.00-0.06), RMS errors (range 2-3%MVC compared to 3-4%MVC), and relative RMS errors (range 10-14%MVC compared to 16-19%MVC) than the task-based predictions. The expanded model predictions of the median and range of amplitude of postures also had consistently better R2 values (range 0.22-0.58 compared to 0.00-0.35), RMS errors (range 2-14 degrees compared to 3-22 degrees), and relative RMS errors (range 9-21 degrees compared to 13-42 degrees) than the task-based predictions. CONCLUSIONS: The variation in physical exposures across users performing the same task is large, especially in comparison to the variation across tasks. Thus, expanded model predictions of physical exposures during computer use should be used rather than task-based predictions to improve exposure assessment for future epidemiological studies. Clinically, this finding also indicates that computer users will have differences in their physical exposures even when performing the same tasks.