Monique H. W. Frings-Dresen

Psychosocial work environment and stress-related disorders, a systematic review

BACKGROUND Knowledge on the impact of the psychosocial work environment on the occurrence of stress-related disorders (SRDs) can assist occupational physicians in the assessment of the work-relatedness of these disorders. AIMS To systematically review the contribution of work-related psychosocial risk factors to SRDs. METHODS A systematic review of the literature was carried out by searching Medline, PsycINFO and Embase for studies published up until October 2008. Studies eligible for inclusion were prospective cohort studies or patient-control studies of workers at risk for SRDs. Studies were included in the review when data on the association between exposure to psychosocial work factors and the occurrence of SRDs were presented. Where possible, meta-analysis was conducted to obtain summary odds ratios of the association. The strength of the evidence was assessed using four levels of evidence. RESULTS From the 2426 studies identified, seven prospective studies were included in this review. Strong evidence was found that high job demands, low job control, low co-worker support, low supervisor support, low procedural justice, low relational justice and a high effort-reward imbalance predicted the incidence of SRDs. CONCLUSIONS This systematic review points to the potential of preventing SRDs by improving the psychosocial work environment. However, more prospective studies are needed on the remaining factors, exposure assessment and the relative contributions of single factors, in order to enable consistent assessment of the work-relatedness of SRDs by occupational physicians.

Stressful work, psychological job strain, and turnover: A 2-year prospective cohort study of truck drivers

Based on a model that combines existing organizational stress theory and job transition theory, this 2-year longitudinal study examined antecedents and consequences of turnover among Dutch truck drivers. For this purpose, self-reported data on stressful work (job demands and control), psychological strain (need for recovery after work and fatigue), and turnover were obtained from 820 drivers in 1998 and 2000. In agreement with the model, the results showed that strain mediates the influence of stressful work on voluntary turnover. Also in conformity with the model, job movement to any job outside the trucking industry (i.e., interoccupational turnover) resulted in a larger strain reduction as compared to job movement within the trucking industry (intraoccupational turnover). Finally, strain was found to stimulate interoccupational turnover more strongly than it stimulated intraoccupational turnover. These findings provide a thorough validation of existing turnover theory and give new insights into the turnover (decision) process.

Considerations of circadian impact for defining 'shift work' in cancer studies : IARC Working Group Report.

Based on the idea that electric light at night might account for a portion of the high and rising risk of breast cancer worldwide, it was predicted long ago that women working a non-day shift would be at higher risk compared with day-working women. This hypothesis has been extended more recently to prostate cancer. On the basis of limited human evidence and sufficient evidence in experimental animals, in 2007 the International Agency for Research on Cancer (IARC) classified ‘shift work that involves circadian disruption’ as a probable human carcinogen, group 2A. A limitation of the epidemiological studies carried out to date is in the definition of ‘shift work.’ IARC convened a workshop in April 2009 to consider how ‘shift work’ should be assessed and what domains of occupational history need to be quantified for more valid studies of shift work and cancer in the future. The working group identified several major domains of non-day shifts and shift schedules that should be captured in future studies: (1) shift system (start time of shift, number of hours per day, rotating or permanent, speed and direction of a rotating system, regular or irregular); (2) years on a particular non-day shift schedule (and cumulative exposure to the shift system over the subjects working life); and (3) shift intensity (time off between successive work days on the shift schedule). The group also recognised that for further domains to be identified, more research needs to be conducted on the impact of various shift schedules and routines on physiological and circadian rhythms of workers in real-world environments.

The effect of office concepts on worker health and performance: a systematic review of the literature

Conventional and innovative office concepts can be described according to three dimensions: (1) the office location (e.g. telework office versus conventional office); (2) the office lay-out (e.g. open lay-out versus cellular office); and (3) the office use (e.g. fixed versus shared workplaces). This review examined how these three office dimensions affect the office workers job demands, job resources, short- and long-term reactions. Using search terms related to the office concept (dimensions), a systematic literature search starting from 1972 was conducted in seven databases. Subsequently, based on the quality of the studies and the consistency of the findings, the level of evidence for the observed findings was assessed. Out of 1091 hits 49 relevant studies were identified. Results provide strong evidence that working in open workplaces reduces privacy and job satisfaction. Limited evidence is available that working in open workplaces intensifies cognitive workload and worsens interpersonal relations; close distance between workstations intensifies cognitive workload and reduces privacy; and desk-sharing improves communication. Due to a lack of studies no evidence was obtained for an effect of the three office dimensions on long-term reactions. The results suggest that ergonomists involved in office innovation could play a meaningful role in safeguarding the workers job demands, job resources and well-being. Attention should be paid, in particular, to effects of workplace openness by providing acoustic and visual protection.

Fear of movement and (re)injury in chronic musculoskeletal pain: Evidence for an invariant two-factor model of the Tampa Scale for Kinesiophobia across pain diagnoses and Dutch, Swedish, and Canadian samples

Abstract The aims of the current study were twofold. First, the factor structure, reliability (i.e., internal consistency), and validity (i.e., concurrent criterion validity) of the Tampa Scale for Kinesiophobia (TSK), a measure of fear of movement and (re)injury, were investigated in a Dutch sample of patients with work‐related upper extremity disorders (study 1). More specifically, examination of the factor structure involved a test of three competitive models: the one‐factor model of all 17 TSK items, a one‐factor model of the TSK (Woby SR, Roach NK, Urmston M, Watson P. Psychometric properties of the TSK‐11: a shortened version of the Tampa Scale for Kinesiophobia. Pain 2005;117:137–44.), and a two‐factor model of the TSK‐11. Second, invariance of the aforementioned TSK models was examined in patients with chronic musculoskeletal pain conditions (i.e., work‐related upper extremity disorders, chronic low back pain, fibromyalgia, osteoarthritis) from The Netherlands, Sweden, and Canada was assessed (study 2). Results from study 1 showed that the two‐factor model of the TSK‐11 consisting of ‘somatic focus’ (TSK‐SF) and ‘activity avoidance’ (TSK‐AA) had the best fit. The TSK factors showed reasonable internal consistency, and were modestly but significantly related to disability, supporting the concurrent criterion validity of the TSK scales. Results from study 2 showed that the two‐factor model of the TSK‐11 was invariant across pain diagnoses and Dutch, Swedish, and Canadian samples. Altogether, we consider the TSK‐11 and its two subscales a psychometrically sound instrument of fear of movement and (re)injury and recommend to use this measure in future research as well as in clinical settings.

Factors associated with long-term sick leave in sick-listed employees: a systematic review

Objective: The objective of this systematic review was to investigate which factors are associated with continued sick leave among workers on sick leave for at least 6 weeks. Methods: A systematic literature search was performed in Medline, EMBASE and PsycINFO, based on combinations of MeSH terms and free text words. Only cohort studies of workers on sick leave for more than 6 weeks at baseline were included. Outcome was measured in terms of factors related to long-term sick leave. The factors were classified first as predisposing, precipitating or perpetuating factors, and then as individual or work-related factors. Methodological quality was assessed for all studies and the strength of the evidence for each factor was assessed using the levels of evidence rating system. Results: Five cohort studies fulfilled all inclusion criteria and 77 factors were investigated. Of these, 16 different significant factors associated with long-term sick leave were identified and were all classified as predisposing factors. Evidence was found for 14 individual factors and two work-related factors. The level of evidence was found to be insufficient for all factors except older age and history of sick leave, which were found to have weak evidence. Conclusions: Based on this review, there is weak evidence that older age and history of sickness absence are factors associated with long-term sick leave in sick-listed employees. There is insufficient evidence for an effect of other individual or work-related factors on long-term sick leave. There are no published studies on perpetuating factors related to long-term sick leave.

Epidemiologic evidence on manual materials handling as a risk factor for back disorders:a systematic review

Abstract In this review, epidemiologic evidence on the role of manual materials handling in the occurrence of back disorders was systematically evaluated. Twenty-five publications that provided quantitative data on associations between manual materials handling and back disorders were selected. Study findings were evaluated on the basis of strength of association, consistency in findings and dose–response relations. The methodological quality of each study was assessed to consider the relative value of the findings. Although a considerable number of epidemiologic studies investigated the risk of lifting, only a moderate insight in the dose–response relation between exposure to lifting and occurrence of back disorders was found. Evidence on carrying and on pushing/pulling as risk factor for back disorders was very limited. Only very few quantitative studies were performed and the results of these studies were inconsistent. The amount of evidence on the risk of exposure to combined manual materials handling was only moderate. It was concluded that, based on the criteria applied in this study, epidemiologic evidence for manual materials handling as risk factor of back disorders is present, but largely based on cross-sectional studies with inherent methodological weaknesses. More longitudinal studies need to be performed in which special attention is given to accurate exposure measurements, valid assessment of back disorders, and dose–response relations. Relevance to industry Manual materials handling is considered a major cause of back disorders in industry. Epidemiologic evidence for the risk of manual materials handling is evaluated, and points of special interest for future epidemiologic studies, which are needed to provide a scientific basis for quantitative guidelines, are discussed.

Need for recovery after work predicts sickness absence: A 2-year prospective cohort study in truck drivers

BACKGROUND Incomplete recovery from work-related fatigue after work (i.e., sustained activation) is assumed to mediate the relation between the exposure to stressful working conditions and the development of health problems. The need for recovery after work scale reflects the extent to which workers have difficulties to recover adequately from work-related fatigue after a working day. OBJECTIVES The aim of this study was to establish if need for recovery after work in truck drivers (1). predicts future sickness absence (>14 working days) and (2). mediates the prospective relation between stressful working conditions (low control, high job demands) and sickness absence. METHODS Self-administered questionnaires, providing information about need for recovery after work, sickness absence, job control, and job demands (psychological, physical, and supervisor job demands), were sent to a random sample of 2000 drivers in 1998. Of the 1123 responders, 820 returned a completed questionnaire 2 years later (response 72%). This study was restricted to the 526 participants who still worked at follow-up as a truck driver at the same company. RESULTS High baseline need for recovery after work was associated with an increased risk for subsequent sickness absence (odds ratio [OR] 2.19, 95% confidence interval [CI] 1.13-4.24) after adjustment for age, previous sickness absence, marital status, educational level, and company size. Additional adjustment for baseline stressful working conditions led to a marginally reduction of the excess risk for sickness absence. CONCLUSIONS High need for recovery after work increases the risk of subsequent sickness absence that is not explained by relevant (non-) work-related factors. However, the results did not testify that need for recovery after work mediates between the exposure to stressful working conditions, and the subsequent occurrence of sickness absence. Practically, the results indicate that monitoring recovery complaints in truck drivers may assist practitioners to take efficient preventive measures at the appropriate time.

Determinants of work ability and its predictive value for disability

BACKGROUND Maintaining the ability of workers to cope with physical and psychosocial demands at work becomes increasingly important in prolonging working life. AIMS To analyse the effects of work-related factors and individual characteristics on work ability and to determine the predictive value of work ability on receiving a work-related disability pension. METHODS A longitudinal study was conducted among 850 construction workers aged 40 years and older, with average follow-up period of 23 months. Disability was defined as receiving a disability pension, granted to workers unable to continue working in their regular job. Work ability was assessed using the work ability index (WAI). Associations between work-related factors and individual characteristics with work ability at baseline were evaluated using linear regression analysis, and Cox regression analysis was used to evaluate the predictive value of work ability for disability. RESULTS Work-related factors were associated with a lower work ability at baseline, but had little prognostic value for disability during follow-up. The hazard ratios for disability among workers with a moderate and poor work ability at baseline were 8 and 32, respectively. All separate scales in the WAI had predictive power for future disability with the highest influence of current work ability in relation to job demands and lowest influence of diseases diagnosed by a physician. CONCLUSION A moderate or poor work ability was highly predictive for receiving a disability pension. Preventive measures should facilitate a good balance between work performance and health in order to prevent quitting labour participation.

The relation between work-induced neuroendocrine reactivity and recovery, subjective need for recovery, and health status

OBJECTIVES The purpose of this cross-sectional study with repeated measurements was to find out to what extent neuroendocrine reactivity during work and neuroendocrine recovery from work, and work characteristics, are related to subjective need for recovery and perceived health status. METHODS Neuroendocrine reactivity and recovery were studied in 59 subjects by measuring urinary adrenaline and cortisol repeatedly during five consecutive days. Measures of work characteristics, subjective need for recovery, and health status were obtained by self-reports. Two hierarchical multiple linear regression analyses were performed. RESULTS The work characteristics alone explained 39% and 28% of the variation in subjective need for recovery and health status, respectively, while these figures rose to 49% and 53% in the full models. Significant neuroendocrine contributors were found for cortisol in reactivity during work and recovery immediately after work and recovery during the day off-work, and for adrenaline in baseline level and recovery during the day off-work. Job characteristics contributed significantly as well. CONCLUSION Both neuroendocrine measures and work characteristics were predictors for the amount of perceived need for recovery after work as well as for health status. The results are consistent with the cognitive activation theory of stress.