Leadership at work and risk of treatment for depressive and anxiety disorders in Denmark. A nationwide prospective study with register-based follow up.

Positive leadership behaviours at work are associated with worker well-being and performance. However there is less knowledge about whether exposure to low levels of positive leadership behaviours increase workers' risk of clinical mental disorders. We investigated whether low levels of positive leadership behaviours are prospectively associated with risk of treatment for depressive and anxiety disorders. In a cohort study, we linked survey data from 59,743 respondents from the Work Environment and Health in Denmark survey with national health register data. Leadership behaviours were measured with an eight-item scale. Treatment was defined as redeemed prescription for antidepressants or anxiolytics or hospital treatment for depression or anxiety. Using Cox proportional hazard regression, adjusting for demographic variables, job type and sector, adverse life events and childhood adversities, we estimated the association between leadership behaviours at baseline and risk of treatment during follow-up. We identified 999 cases of depression and anxiety treatment during follow-up. Compared to high levels of leadership behaviours, exposure to medium low and low levels were associated with an increased risk of treatment after adjustment for covariates. The results suggest that low levels of positive leadership behaviours are associated with an increased risk of treatment for depressive or anxiety disorders.

Work Ability and Work Nonparticipation: A Prospective Study of 2426 Participants in Germany.

OBJECTIVE: The aim of the study is to examine the association between work ability and work nonparticipation, including long-term sickness absence (LTSA), unemployment (UE), and disability pension/early retirement (ER). METHODS: We conducted a questionnaire-based 5-year follow-up study on a representative sample of the German working population (n = 2426). We used a two-part model to examine the association of continuous Work Ability Index (WAI) scores with the probability of events of work nonparticipation and the duration thereof. RESULTS: Higher WAI scores were protective against total work nonparticipation (an index combining the three indicators), LTSA, ER and UE, the latter among males only. Higher WAI scores were protective also against duration of total work nonparticipation and LTSA, but not against duration of UE and ER among males and duration of UE among females. CONCLUSIONS: Higher WAI scores have a protective role against work nonparticipation.

Associations between depressive symptoms and 5-year subsequent work nonparticipation due to long-term sickness absence, unemployment and early retirement in a cohort of 2,413 employees in Germany.

BACKGROUND: We examined the association of depressive symptoms with subsequent events - and duration thereof - of work nonparticipation (long-term sickness absence, unemployment and early retirement). METHODS: We employed a 5-year cohort from the Study on Mental Health at Work (S-MGA), based on a random sample of employees subject to social contributions aged 31-60 years in 2012 (N = 2413). Depressive symptoms were assessed at baseline through questionnaires, while work nonparticipation was recorded in follow-up interviews. Associations of depressive symptoms with subsequent events of work nonparticipation were examined in two-part models, with events analysed by logistic regressions and their duration by generalized linear models. RESULTS: Medium to severe depressive symptoms were associated with events of work nonparticipation (males Odds Ratio [OR] = 3.22; 95% CI = 1.90-5.45; females OR = 1.92; 95% CI = 1.29-2.87), especially with events of long-term sickness absence in both genders and events of unemployment in males. Mild depressive symptoms were also associated with events of work nonparticipation (males OR = 1.59; 95% CI = 1.19-2.11; females OR = 1.42; 95% CI = 1.10-1.84). Among those experiencing one or more events, the duration of total work nonparticipation was twice as high among males [Exp(ß) = 2.06; 95% CI = 1.53-2.78] and about one third higher [Exp(ß) = 1.38; 95% CI = 1.05-1.83] among females with medium to severe depressive symptoms. CONCLUSIONS: The present study focuses on both events and duration of work nonparticipation, which are both critical for examining societal consequences of depressive symptoms. It is key to regard also mild depressive symptoms as a possible risk factor and to include different types of work nonparticipation.

Association of workplace violence and bullying with later suicide risk: a multicohort study and meta-analysis of published data.

BACKGROUND: Workplace offensive behaviours, such as violence and bullying, have been linked to psychological symptoms, but their potential impact on suicide risk remains unclear. We aimed to assess the association of workplace violence and bullying with the risk of death by suicide and suicide attempt in multiple cohort studies. METHODS: In this multicohort study, we used individual-participant data from three prospective studies: the Finnish Public Sector study, the Swedish Work Environment Survey, and the Work Environment and Health in Denmark study. Workplace violence and bullying were self-reported at baseline. Participants were followed up for suicide attempt and death using linkage to national health records. We additionally searched the literature for published prospective studies and pooled our effect estimates with those from published studies. FINDINGS: During 1 803 496 person-years at risk, we recorded 1103 suicide attempts or deaths in participants with data on workplace violence (n=205 048); the corresponding numbers for participants with data on workplace bullying (n=191 783) were 1144 suicide attempts or deaths in 1 960 796 person-years, which included data from one identified published study. Workplace violence was associated with an increased risk of suicide after basic adjustment for age, sex, educational level, and family situation (hazard ratio 1·34 [95% CI 1·15-1·56]) and full adjustment (additional adjustment for job demands, job control, and baseline health problems, 1·25 [1·08-1·47]). Where data on frequency were available, a stronger association was observed among people with frequent exposure to violence (1·75 [1·27-2·42]) than occasional violence (1·27 [1·04-1·56]). Workplace bullying was also associated with an increased suicide risk (1·32 [1·09-1·59]), but the association was attenuated after adjustment for baseline mental health problems (1·16 [0·96-1·41]). INTERPRETATION: Observational data from three Nordic countries suggest that workplace violence is associated with an increased suicide risk, highlighting the importance of effective prevention of violent behaviours at workplaces. FUNDING: Swedish Research Council for Health, Working Life and Welfare, Academy of Finland, Finnish Work Environment Fund, and Danish Working Environment Research Fund.

Is a Positive Intergenerational Workplace Climate Associated with Better Self-Perceived Aging and Workplace Outcomes? A Cross-Sectional Study of a Representative Sample of the Danish Working Population.

The aim of this study was to determine the association between intergenerational workplace climate (attitudes, feelings, and perceptions about workers of different ages in the workplace) and self-perceived aging, work engagement, and turnover intention. A cross-sectional study was conducted via an online survey including answers from a representative sample of 1571 individuals aged 18-74 years, living and working in Denmark. In line with our hypotheses, we found that a more positive intergenerational workplace climate was related to a better self-perceived aging as well as to more work engagement and less turnover intention. In addition, we found that these associations were similar in all age groups. The findings point to the potential benefits of initiatives aimed at strengthening the intergenerational climate in workplaces.

Long-term associations of psychosocial working conditions with depressive symptoms and work-related emotional exhaustion: comparing effects in a 5-year prospective study of 1949 workers in Germany.

OBJECTIVE: To test the hypothesis that psychosocial working conditions are more strongly associated with subsequent work-related emotional exhaustion (core component of burnout) than with depressive symptoms at follow-up. METHODS: A 5-year cohort study (2011/2012-2017), based on a random sample of persons in employment subject to payment of social contributions aged 31-60 years (Study on Mental Health at Work; S-MGA; N = 1949), included self-reported measures of organisational demands (organisational layoffs and restructuring), task-level demands (work pace and amount of work) and job resources (influence at work, possibilities for development, control over working time, role clarity), all taken from the COPSOQ, except the organisational demands that were single-item measures. Work-related emotional exhaustion and depressive symptoms were measured with the Oldenburg Burnout Inventory and the Patient Health Questionnaire-9, respectively. RESULTS: Cochrane Q tests revealed stronger associations between psychosocial working conditions and work-related emotional exhaustion only for the amount of work (p = 0.013) and control over working time (p = 0.027). No differences were observed for the Demands and Resources Indexes, capturing overall exposure to psychosocial working conditions. The same differences were observed in a subsample including only participants who remained at the same employer from baseline to follow-up, although more psychosocial working conditions were associated with work-related emotional exhaustion than with depressive symptoms. Supplementary analyses employing dichotomous measures of work-related emotional exhaustion and depressive symptoms confirmed these results. CONCLUSIONS: Overall, the findings provide limited evidence supporting the hypothesis that psychosocial working conditions are more strongly associated with work-related emotional exhaustion than with depressive symptoms.

Negative Acts as Risk Factor for Work-Related Violence and Threats from Clients towards Employees: A Follow-Up Study.

BACKGROUND: Work-related violence and threats are major problems in many occupations, especially within the human service sector, with consequences at multiple levels, including reduced physical and mental health, increased absenteeism, and reduced organizational commitment. It is, therefore, crucial to identify risk factors for work-related violence and threats. However, only a few studies have examined whether negative acts at work increase the risk of work-related violence and threats from clients toward employees. OBJECTIVE: To examine the associations between exposure to negative acts towards employees from colleagues, clients, or a combination of both, and the risk of work-related violence and threats perpetrated by clients towards employees in a longitudinal study. METHODS: Questionnaire data were collected in 2010, 2011, and 2015. In total, 5333 employees from special schools, psychiatric wards, eldercare, and the Prison and Probation Services participated in the first round of data collection in 2010. Negative acts were measured in 2010 using the Short Negative Acts Questionnaire, while work-related threats and violence were measured at all three-time points. The analyses were performed using multilevel logistic regression. RESULTS: Negative acts from clients and the combination of negative acts from both clients and colleagues were associated with later exposure to work-related violence and threats. The associations were observed after one year, and work-related threats were still present after four years. CONCLUSION AND IMPLICATIONS: Negative acts are associated with an increased risk of work-related violence and threats perpetrated by clients toward employees. Organizations may reduce the risk of work-related violence and threats by preventing negative acts.

Leadership behaviours and health-related early exit from employment: a prospective cohort study of 55 364 employees.

BACKGROUND: Absence of certain leadership behaviours, such as lack of feedback, recognition and involvement in employee development, has been associated with long-term sickness absence. We tested the hypothesis that absence of eight specific behaviours predicts health-related early exit from employment, and investigated differential effects in subgroups to guide future preventive initiatives. METHODS: Using Cox-proportional hazard modelling, we examined the prospective association between absence of leadership behaviours and health-related early exit from employment in a sample of 55 364 employees during 4.3 years follow-up. Leadership behaviours were measured by employee ratings in national surveys from 2012 to 2016. Exit from employment included disability pension and related measures of health-related early exit, retrieved from a national registry. RESULTS: We identified 510 cases of health-related early exit from employment during follow-up. A high level of absence of leadership behaviours, was associated with an increased risk of exit from employment (hazard ratio: 1.57, 95% CI: 1.31; 1.89). Subgroup analyses showed that the association between absence of leadership behaviours and exit from employment was similar for women and men and across age groups. The association was stronger for employees with high level of education than for employees with medium/low education, and the association was not observed among employees with a prevalent depressive disorder. CONCLUSIONS: Absence of the eight leadership behaviours is a risk factor for health-related early exit from employment in the Danish workforce. More studies are needed to confirm the results.

Workplace bullying and risk of suicide and suicide attempts: A register-based prospective cohort study of 98 330 participants in Denmark.

OBJECTIVES: The aim of this study was to analyze whether individuals reporting exposure to workplace bullying had a higher risk of suicidal behavior, including both suicide attempt and death by suicide, than those not reporting such exposure. METHODS: Using a prospective cohort study design, we linked data from nine Danish questionnaire-based surveys (2004-2014) to national registers up to 31 December 2016. Exposure to workplace bullying was measured by a single item. Suicide attempts were identified in hospital registers and death by suicide in the Cause of Death Register. Among participants with no previous suicide attempts, we estimated hazard ratios (HR) and 95% confidence intervals (CI), adjusting for sex, age, marital status, socioeconomic status, and history of psychiatric morbidity. RESULTS: The sample consisted of 98 330 participants (713 798 person-years), 63.6% were women, and the mean age was 44.5 years. Of these participants, 10 259 (10.4%) reported workplace bullying. During a mean follow-up of 7.3 years, we observed 184 cases of suicidal behavior, including 145 suicide attempts, 35 deaths by suicide and 4 cases that died by suicide after surviving a suicide attempt. The fully-adjusted HR for the association between workplace bullying and suicidal behavior was 1.65 (95% CI 1.06-2.58). The HR for suicide attempts and death by suicide were 1.65 (1.09-2.50) and 2.08 (0.82-5.27), respectively. Analyses stratified by sex showed a statistically significant association between workplace bullying and suicidal behavior among men but not women. CONCLUSIONS: The results suggest that exposure to workplace bullying is associated with an elevated risk of suicidal behavior among men.

Workplace Bullying and Long-Term Sickness Absence-A Five-Year Follow-Up Study of 2476 Employees Aged 31 to 60 Years in Germany.

OBJECTIVES: The aim was to investigate workplace bullying as a risk factor for five-year occurrence of long-term sickness absence (LTSA) in a representative cohort of employees in Germany. METHODS: In the German Study on Mental Health at Work (S-MGA) (n = 2476), episodes of long-term sickness absence (LTSA) between baseline and follow-up were assessed in the follow-up interview. Workplace bullying was measured in the baseline interview using a hybrid approach, which combines the behavioural experience and self-labelling methods. Through binomial regressions, the association of baseline level of workplace bullying with first-episode LTSA during follow-up was estimated, adjusting for baseline age, gender, occupational level, smoking status and physical demands at work. RESULTS: Severe bullying heightened the risk for LTSA by approximately 50% (Rate ratio-RR: 1.48, 95% Confidence interval-CI: 1.05; 2.19), while occasional bullying heightened the risk by 15% (RR: 1.15, CI: 0.85; 1.55). When excluding LTSA events occurring in the first 2 years, the associations between bullying and LTSA increased by approximately one third. CONCLUSIONS: Workplace bullying seems to be a risk factor for LTSA even when controlling for occupational level, smoking and physical demands at work and when taking possible reverse causality into account. We suggest to investigate effects of LTSA in more settings, to distinguish between occasional and severe bullying and employ longer follow-up intervals.

Precarious Work as Risk Factor for 5-Year Increase in Depressive Symptoms.

OBJECTIVES: The aim was to investigate the longitudinal relationship between precarious work and depressive symptoms in a representative cohort of employees in Germany. METHODS: In the German Study on Mental Health at Work (S-MGA) (n = 2009), depressive symptoms were assessed by the Patient Health Questionnaire (PHQ-9). Precarious work was measured through baseline (2012) self-reported job insecurity, marginal part-time, fixed-term contract, hourly wage and-during follow-ups 2012-2017-unemployment. Among employees without depressive symptoms at baseline (2012), we ran logistic regression analyses stratified by gender with depressive symptoms at follow-up in 2017 as the dependent variable, adjusting for baseline (2012) age, gender, socioeconomic position and partner status. RESULTS: Among men, job insecurity (OR: 2.47; 95% 95% CI: 1.37-4.48) and low wage (3.79; 1.64-8.72) at baseline were significantly associated with depressive symptoms at follow-up. Among women, indicators of precarious work were not associated with depressive symptoms at follow-up. Among men, a cumulative exposure index of precarious work was significantly associated with the development of depressive symptoms (one indicator: 1.84; 0.94-3.60, ≥two indicators: 7.65; 3.30-17.73). This index was not associated with depressive symptoms among women. The population attributable fraction of precarious work due to depressive symptoms among men was approximately 30%. CONCLUSIONS: Among employees in Germany, precarious work seems to be a risk factor for the subsequent development of depressive symptoms among men, but not among women. Research on precarious employment in different countries is needed.

Physical and psychosocial working conditions as predictors of 5-year changes in work ability among 2078 employees in Germany.

OBJECTIVE: To examine 5-year prospective associations between working conditions and work ability among employees in Germany. METHODS: A cohort study (2011/2012-2017), based on a random sample of employees in employments subject to payment of social contributions aged 31-60 years (Study on Mental Health at Work; S-MGA; N = 2,078), included data on physical and quantitative demands, control (influence, possibilities for development, control over working time), relations (role clarity and leadership quality) and work ability (Work Ability Index, WAI; subscale 'subjective work ability and resources'). Data were analysed using linear regression. RESULTS: Physical demands and control were associated with small 5-year changes in work ability (ΔR2 = 1%). Among the subgroup of employees with ≥ 25 sickness days, possibilities for development, control and quality of leadership were associated with changes in work ability (ΔR2 = 8%). CONCLUSIONS: The impact of working conditions on long term changes in work ability seems to be negligible. However, in vulnerable subpopulations experiencing poor health, working conditions may be associated to a larger extent to work ability over this time span.

Antecedents of Workplace Bullying among Employees in Germany: Five-Year Lagged Effects of Job Demands and Job Resources.

OBJECTIVES: The aim of the present study was to examine the long-term association of job demands and job resources with self-reported exposure to workplace bullying in a representative sample of employees in Germany. METHODS: We analysed a nation-wide representative cohort of employees working in the same workplace with a 5-year follow-up (S-MGA; N = 1637). The study contained self-reported measures of psychosocial working conditions, including work pace, amount of work, influence at work, role clarity and quality of leadership, and workplace bullying, and of organisational factors, including organisational restructuring and layoffs. RESULTS: After controlling for bullying and occupational level at baseline, higher baseline levels of organisational restructuring (OR 1.73; 95% CI 1.10-2.70), work pace (1.30; 95% CI 1.01-1.66), and amount of work (1.55; 95% CI 1.21-1.99), and lower baseline levels of influence at work (0.70; 95% CI 0.55-0.90) and quality of leadership (0.64; 95% CI 0.50-0.82), were associated with an elevated risk of workplace bullying at follow-up. In all, 90% of cases of self-reported workplace bullying could be attributed to these factors. CONCLUSIONS: The study suggests that employees reporting higher demands and lower resources, as well as organisational factors such as restructuring, are at a higher long-term risk of being targets of workplace bullying. Interventions aimed at preventing workplace bullying could benefit from a focus on psychosocial working conditions and organisational factors.

Deployment experiences and mental health problems as predictors of post-deployment unemployment length: a prospective, register-based study among Danish soldiers.

OBJECTIVES: To test responses of formerly deployed soldiers (FDS) to a questionnaire on deployment experiences in combination with screening levels of post-traumatic stress disorder (PTSD) and depression approximately 6 months after homecoming as predictors of the subsequent probability of gaining employment when unemployed within 5 years post-deployment. DESIGN, SETTING AND PARTICIPANTS: Danish FDS responders (n=3935) and non-responders (n=3046) to a 6-month post-deployment screening questionnaire after returning from a first-ever deployment to Kosovo, Iraq or Afghanistan (2002 to 2012) were included in the study and followed in public registers from 6 months to 5 years post-deployment. PRIMARY AND SECONDARY OUTCOME MEASURES: We tested Cox regression models including deployment experiences (1a), screening levels of PTSD and depressive symptoms (1b), and their combination (2) for FDS responders. For all FDS, a secondary model included a measure on whether they responded to the questionnaire (3). RESULTS: Neither the deployment experiences (1a) of exposure to danger and combat (HR=1.00, 95% CI=0.97 to 1.03) and witnessing consequences of war (HR=1.01, 95% CI=0.96 to 1.06), or the screening levels (1b) of PTSD (HR=1.06, 95% CI=0.84 to 1.33) and depressive symptoms (HR=0.82, 95% CI=0.64 to 1.06) were significant predictors of transitioning from unemployment to employment. Similar results were found for the combined model (2). A tendency among non-respondents (3) to have a lower probability of transitioning from unemployment to employment was found (HR=0.90, 95% CI=0.81 to 1.00). CONCLUSION: Deployment experiences, PTSD and depressive symptoms, as measured at 6-month screening questionnaire, did not predict differences in the probability of gaining employment when unemployed within 5 years post-deployment. However, the findings suggest that those with the least probability of transitioning from unemployment to employment can be found among the non-responders to the post-deployment screening questionnaire.

The Demand-Control model and work-related threats and violence: Short- and long-term associations.

BACKGROUND: Work-related violence and threats are frequent in human service sectors. Although previous studies have identified several psycho-social work environmental risk factors for work-related violence and threats, the research domain still remains mainly descriptive and non-theoretical in nature. OBJECTIVE: Using the Job-Demands-Control model we analysed the relationship between the psycho-social work environment and work-related threats and violence. METHOD: Using a two-wave (2011 and 2015) longitudinal study of 2678 participants, we analysed the main and interactive effects of quantitative demands and job control on exposure to work-related violence and threats. RESULTS: High work demands and low job-control were associated with elevated risk of work-related threats in 2011 and in 2015. The associations of work demands and job control and work-related violence were mixed. There were not statistically significant interaction effects between high demands and low job control on neither work-related violence nor threats. CONCLUSION: In sectors where work-related threats and violence are likely to occur, risk prevention may also require improving the work conditions for employees, more specifically by reducing work-demands and increasing job control for instance by differentiating between important and less important work demands and by implementing self-autonomous work-teams may be a way to increase job control.

Workplace bullying and depressive symptoms among employees in Germany: prospective associations regarding severity and the role of the perpetrator.

OBJECTIVES: The aim of this study was to investigate the effect of self-reported workplace bullying on depressive symptoms in a prospective study among a representative sample of employees from Germany. We focused specifically on the role of the perpetrator (co-workers and superiors), which was never done before in a longitudinal design. METHODS: We used data from a nation-wide representative panel study with a 5-year follow-up (N = 2172). Data on bullying exposure were obtained separately for different perpetrators (co-workers and superiors) and degree of severity (severe bullying, i.e., at least weekly). Depressive symptoms were assessed with the Patient Health Questionnaire (PHQ). We used logistic regression analyses to examine the effect of workplace bullying at baseline on depressive symptoms at follow-up. RESULTS: After adjusting for baseline depressive symptoms, severe bullying by co-workers significantly increased the 5-year risk of depressive symptoms (OR = 2.50). Severe bullying by superiors had a nonsignificant effect. CONCLUSIONS: Workplace bullying is a risk factor for depressive symptoms among employees in Germany. The type of perpetrator seems to be an important factor to consider, as indicated by the elevated risk of depressive symptoms when bullying is perpetrated by co-workers.

Does leadership support buffer the effect of workplace bullying on the risk of disability pensioning? An analysis of register-based outcomes using pooled survey data from 24,538 employees.

PURPOSE: To investigate whether self-reported exposure to workplace bullying predicts the risk of disability pensioning among employees in two occupational groups-(1) employees working with clients or customers and (2) office workers and manual workers-and whether leadership support and occupational group moderates that association. METHODS: Survey data from 24,538 employees (112,889 person years) were fitted to a national register containing information on disability-pension payments. Using multi-adjusted Cox-regression analysis, observations were followed in the register to assess the risk of disability pensioning. The average follow-up time was 4.6 years (standard deviation [SD] = 1.5). RESULTS: Self-reported exposure to workplace bullying predicted an increased risk of disability pensioning (hazard ratio [HR] = 1.46; 95% confidence interval [CI]: 1.15-1.86). This association was moderated by leadership support: the association between workplace bullying and disability pensioning was significantly different for respondents who reported low leadership support (HR = 1.97; 95% CI: 1.38-2.80) compared to respondents who reported medium (HR = 1.03; 95% CI: 0.60-1.76) or high leadership support (HR = 1.08; 95% CI: 0.60-1.95). Further analyses showed similar associations between workplace bullying and the risk of disability pensioning among the two occupational groups. CONCLUSIONS: Self-reported workplace bullying increases the risk of disability pensioning, and this association is buffered by leadership support. Workplace bullying should be considered an important workplace stressor. This study indicates that workplaces may enhance worker retention by actively promoting measures to eliminate the occurrence of workplace bullying and to enhance leadership support.

Workplace bullying among employees in Germany: prevalence estimates and the role of the perpetrator.

OBJECTIVES: The aim of this study was to examine the prevalence of workplace bullying in Germany while also taking the perpetrator and severity level (measured by frequency) into account and considering the role of gender, age and socio-economic status. METHODS: We used data from a large representative sample (N = 4143) of employees in Germany subject to social security contributions. Self-reported bullying was assessed for different combinations of perpetrators (co-workers, superiors) and according to severity, i.e., being exposed at all and to severe bullying (at least weekly). RESULTS: Prevalence estimates varied from 2.9% for severe bullying by co-workers to 17.1% for overall bullying (i.e., without distinguishing by perpetrator, less severe bullying also included). Unskilled workers reported more bullying by both perpetrators than academics/managers. We also observed an age trend for severe bullying by superiors (i.e., bossing), with younger employees being more affected from bossing than elder. No gender differences were detected. CONCLUSIONS: The findings indicate that it is crucial to consider type of perpetrator and severity of the behaviors when examining the prevalence of workplace bullying. The way bullying is defined and operationalized strongly contributes to the prevalence estimates. Differences between subgroups and associations or cause-effect relationships should be analyzed with these variations in mind.

A cohort study on self-reported role stressors at work and poor sleep: does sense of coherence moderate or mediate the associations?

AIM: The aim of the present study was to examine the bidirectional associations between subjective role ambiguity and role conflicts at work, respectively, and self-reported sleep 2 years later. In addition, we also examine whether sense of coherence (SOC) moderate or mediate the association between role stressors and poor sleep and between poor sleep and role stressors. METHODS: We used questionnaire data collected in 2006 and 2008 from the Workplace Bullying and Harassment cohort. In 2006, 3363 responded to the questionnaire and in 2008 1671 responded. In total, 1569 participants responded in both 2006 and 2008 to the questions on role stressors (in terms of role ambiguity and role conflicts at work) and sleep problems in both 2006 and 2008. Sleep problems were assessed with the awakening index (AWI) and the disturbed sleep index (DSI). Moderation and mediation analyses of the association were estimated using structural equation modelling. RESULTS: We found a prospective association between role stressors and sleep problems [beta values were 0.07 (95% CI 0.03-0.11) and 0.05 (CI 0.01-0.10) for DSI and AWI, respectively] when adjusting for sleep problems at baseline, age, sex, and life style factors (i.e. alcohol, smoking, and leisure time physical activity). SOC moderated the association showing that participants with lower SOC scores who reported higher role ambiguity reported sleep problems to a higher extent than participants with high SOC scores. SOC also mediated the association between role stressors and sleep problems. We also found support for sleep problems at baseline and role stressors 2 years later [DSI 0.04 (CI 0.00-0.08) and 0.15 (CI 0.09-0.21)] for role ambiguity and role conflicts, respectively. Similar results were observed for AWI. CONCLUSION: Subjective role stressors were prospectively associated with sleep problems. Yet, sleep problems could also prospectively predict subjective role stressors (i.e. reverse causation). The analyses also showed that SOC may be regarded as both a mediating and a moderating factor of the association between subjective role conflicts and poor sleep. We found that SOC moderated the prospective association so participants with low SOC report more sleep problems with subjective role conflicts compared to participants with high SOC. Finally, we also found SOC mediated the prospective association between subjective role stressors and sleep problems and the reverse association.

Optimal Cut-Off Points for the Short-Negative Act Questionnaire and Their Association with Depressive Symptoms and Diagnosis of Depression.

Objectives: The behavioural experience method has been extensively used in the literature for the measurement of potential bullying behaviours at work. However, this approach presents limitations when used to classify respondents as targets or non-targets of workplace bullying. Therefore, the present study aimed to: (i) identify optimal cut-off points, reflecting a possible subjectively experienced exposure to occasional and frequent workplace bullying, for the 9-item Short Negative Act Questionnaire (S-NAQ), and (ii) examine the criterion validity of these cut-off points in relation to depressive symptoms and diagnosis of depression. Methods: The study was based on a sample of 4882 participants from the Danish MODENA cohort study (year 2011), which included both the S-NAQ (score range 9-45) and a one-item measure applying the self-labelling method with a definition to assess occasional and frequent workplace bullying. We employed receiver operating characteristic (ROC) curve analyses to derive the cut-off points for the S-NAQ. Based on these cut-off points, we created a new S-NAQ variable with three levels of exposure (i.e. 'not exposed', 'first threshold', and 'second threshold') and tested its criterion validity in relation to depressive symptoms (N = 4071) and diagnosis of depression (N = 4844). Results: The S-NAQ cut-off points obtained were ≥12 and ≥16 when using occasional and frequent bullying as reference standards, respectively. Both cut-off points showed high classification accuracy (area under the curve = 0.89 and 0.93) as well as good sensitivity (84.8% and 88.0%) and specificity (77.4% and 94.7%). In the adjusted linear regression analyses, both the first (B = 0.78, 95% confidence interval [CI] = 0.66-0.90) and the second threshold of exposure (B = 1.65, 95% CI = 1.44-1.86) were significantly associated with depressive symptoms. In the adjusted logistic regression analyses, both the first (odds ratio [OR] = 3.55, 95% CI = 1.98-6.38) and the second threshold of exposure (OR = 5.90, 95% CI = 2.93-11.88) were significantly associated with diagnosis of depression. Conclusions: The two cut-off points for the S-NAQ identified in this study showed a significant association with both depressive symptoms and diagnosis of depression. However, future prospective studies are needed to establish the predictive validity of the proposed cut-off points.