The effect of objective job demands on registered sickness absence spells; do personal,social and job-related resources act as moderators?

Abstract

This study applied Karaseks demand-control model, using sense of coherence (SOC), social support and job control as moderators of effects of job demands on ensuing sickness absence spells in a 3-year follow-up of 856 municipal employees. Among men the results supported the active learning hypothesis. Passive jobs predicted a high number of sickness absence spells and active jobs predicted a low number of spells. for short spells (1-3 days), the demand-control interaction, however, depended on SOC. In active jobs SOC was negatively associated with sickness absence spells; in passive jobs no such association was found. For long spells (3 days), the demand-control interaction depended on occupational level; active jobs were predictive of low absence spells among blue collar men. Among women, the results supported the strain hypothesis. The demand-control interaction, however, depended on household size. In small households, high-strain jobs predicted a high number of spells, while no increase in spells was found in active versus low-strain jobs. In larger households, the number of spells correlated positively with increasing demands even when control was good. The demand-control interaction, however, depended on SOC and spouse support. With strong SOC or spouse support, absence spells in active jobs remained on a relatively low level, otherwise active jobs led to a high number of spells. This suggests that SOC and spouse support may act as protective factors against female role conflicts associated with active jobs     

The effects of new dimensions of psychological job demands and job control on active learning and occupational health

Recent changes in job content may have led to changes in job demands and control, and earlier operationalizations of the demand concept may be too general (MT). The aim of this paper is to show how new dimensions of psychological job demands are related to two sets of outcome variables, employee health and active learning, and how these relationships are modified or interact with social support and types of job control. The study was carried out as a survey among employees of 13 electric companies in Norway, N=2435. Lisrel was used to assess the fit of the proposed models. Compared to the traditional demands control model, an extended version used in this study increased the explained variance on an average by 4% on various occupational health variables. It was found that various dimensions of demands were differentially related to the outcome variables. Skill discretion uniformly reduced the effect of the demands: for groups low in skill discretion there was a stronger relationship between demands and outcomes than for groups high in skill discretion. The interaction pattern for the remaining control and support variables was however more complicated and warrants further study. The practical implications are that employers should carefully consider the quality of work. Special attention should be given to the quantitative demands of the jobs, since there seems to be few moderators for the relationship between those demands and job stress and subjective health complaints.     

The effects of new dimensions of psychological job demands and job control on active learning and occupational health

Abstract

Recent changes in job content may have led to changes in job demands and control, and earlier operationalizations of the demand concept may be too general (MT). The aim of this paper is to show how new dimensions of psychological job demands are related to two sets of outcome variables, employee health and active learning, and how these relationships are modified or interact with social support and types of job control. The study was carried out as a survey among employees of 13 electric companies in Norway, N=2435. Lisrel was used to assess the fit of the proposed models. Compared to the traditional demands control model, an extended version used in this study increased the explained variance on an average by 4% on various occupational health variables. It was found that various dimensions of demands were differentially related to the outcome variables. Skill discretion uniformly reduced the effect of the demands: for groups low in skill discretion there was a stronger relationship between demands and outcomes than for groups high in skill discretion. The interaction pattern for the remaining control and support variables was however more complicated and warrants further study. The practical implications are that employers should carefully consider the quality of work. Special attention should be given to the quantitative demands of the jobs, since there seems to be few moderators for the relationship between those demands and job stress and subjective health complaints.     

The Job Demand-Control (-Support) Model and psychological well-being: A review of 20 years of empirical research

The Job Demand-Control (JDC) model (Karasek, 1979) and the Job Demand-Control-Support (JDCS) model (Johnson, and Hall, 1988) have dominated research on occupational stress in the last 20 years. This detailed narrative review focuses on the JDC(S) model in relation to psychological well-being. It covers research from 63 samples, published in the period 1979-1997. In the review a distinction is drawn between two different hypotheses prevailing in research on the models. According to the strain hypothesis of the JDC model, employees working in a high-strain job (high demands-low control) experience the lowest well-being. The buffer hypothesis states that control can moderate the negative effects of high demands on well-being. Translating these hypotheses to the expanded JDCS model, the iso-strain hypothesis predicts the most negative outcomes among workers in an iso-strain job (high demands-low control-low social support/isolation), whereas the buffer hypothesis states that social support can moderate the negative impact of high strain on well-being. Although the literature gives considerable support for the strain and iso-strain hypotheses, support for the moderating influence of job control and social support is less consistent. The conceptualization of demands and control is a key factor in discriminating supportive from nonsupportive studies. Only aspects of job control that correspond to the specific demands of a given job moderate the impact of high demands on well-being. Furthermore, certain subpopulations appear to be more vulnerable to high (iso)strain, whereas others benefit more from high control. On the basis of the results of this review, suggestions for future research and theoretical development are formulated.     

The Job Demand-Control (-Support) Model and psychological well-being: a review of 20 years of empirical research

The Job Demand-Control (JDC) model (Karasek, 1979) and the Job Demand-Control-Support (JDCS) model (Johnson, and Hall, 1988) have dominated research on occupational stress in the last 20 years. This detailed narrative review focuses on the JDC(S) model in relation to psychological well-being. It covers research from 63 samples, published in the period 1979-1997. In the review a distinction is drawn between two different hypotheses prevailing in research on the models. According to the strain hypothesis of the JDC model, employees working in a high-strain job (high demands-low control) experience the lowest well-being. The buffer hypothesis states that control can moderate the negative effects of high demands on well-being. Translating these hypotheses to the expanded JDCS model, the iso-strain hypothesis predicts the most negative outcomes among workers in an iso-strain job (high demands-low control-low social support/isolation), whereas the buffer hypothesis states that social support can moderate the negative impact of high strain on well-being. Although the literature gives considerable support for the strain and iso-strain hypotheses, support for the moderating influence of job control and social support is less consistent. The conceptualization of demands and control is a key factor in discriminating supportive from nonsupportive studies. Only aspects of job control that correspond to the specific demands of a given job moderate the impact of high demands on well-being. Furthermore, certain subpopulations appear to be more vulnerable to high (iso)strain, whereas others benefit more from high control. On the basis of the results of this review, suggestions for future research and theoretical development are formulated.     

Testing Karasek's learning and strain hypotheses on young workers in their first job

This study tests the core hypotheses of Karasek's job demand-control model: high job demands (workload) in combination with low job control (autonomy) increase strains (job dissatisfaction; strain hypothesis), whereas high job demands in combination with high job control increase learning and development in the job (here: learning new skills in the first job; learning hypothesis). These hypotheses are tested in two ways: (a) the mere combination of both job characteristics is associated with the expected outcomes, and (b) a statistical interaction between both job characteristics in predicting the outcomes is expected. A large dataset (n=2,212) of young workers in their first job was used to test all hypotheses. As young workers are presumably still in the process of adjusting themselves to their work environment, we expected that the effects of work characteristics on work outcomes would be stronger for this group than for more experienced workers. The results confirm both the strain and the learning hypothesis. We found a combined effect of both job characteristics, as well as a statistical interaction between both variables. The lowest level of job satisfaction was found in the “high strain” job, whereas the highest increase in skills was found in the “active” job. The consequences of these findings for theory and practice are discussed.     

The moderating role of social support in Karasek's job strain model

This paper examines whether social support is a boundary-determining criterion in the job strain model of Karasek (1979). The particular focus is the extent to which different sources of social support, work overload and task control influence job satisfaction, depersonalization and supervisor assessments of work performance. Hypotheses are tested using prospective survey data from 80 clerical staff in a university setting. Results revealed 3-way interactions among levels of support (supervisor, co-worker, non-work), perceived task control and work overload on levels of work performance and employee adjustment (self-report). After controlling for levels of negative affect in all analyses, there was evidence that high levels of supervisor support mitigated against the negative effects of high strain jobs on levels of job satisfaction and reduced reported levels of depersonalization. Moreover, high levels of non-work support and co-worker support also mitigated against the negative effects of high strain jobs on levels of work performance. The results are discussed in terms of the importance of social support networks both at, and beyond, the work context.     

Job design and levels of physical and mental strain among Australian prison officers

Over the past 15 years much has been made of the moderating influence of job discretion and support in occupations that are perceived to be high in demands. Such an effect seems to be most prevalent when subject populations are large and heterogeneous. One aim of this study was to examine the influence of subjective perceptions of these variables on strain reactions among a group of relatively homogeneous workers such as, in the present study, prison officers (n = 274). A second aim was to extend previous research and examine the joint influence of negative affectivity and perceptions of demands, discretion, and support on mental and physical well-being. It was hypothesized that those high in negative affect would be particularly strained by jobs perceived as being demanding. The hypothesized relationship between job demands, discretion and support were found to be weak and at times inconsistent. Social support, in particular, was found to have both positive and negative consequences for different aspects of well-being. Those high in negative affect were in general found to suffer lower mental well-being. More importantly, the interactive effect of negative affectivity and job demands was found to significantly predict the majority of the dependent variables used in this study. The valences of these relationships were inconsistent and are interpreted in light of Warr's (1987) vitamin model of stress.

There are several conclusions that can be drawn from the present study. Negative affectivity appears to have a truly interactive effect with job components, job demands in particular, to influence a range of variables relating to physical and mental health as well a job-related attitudes. The nature of these effects, however, suggests a dissociation in the ways that different independent variables influence a range of indices of well-being and affect. This result requires further investigation since there are important theoretical implications which will follow if the data are replicable.

In order to examine such complex effects, in addition to the need for more longitudinal studies, it is also important that standardized measures of job components are developed so that levels of stress exposure can be equated and their impact assessed across organizational settings.

Finally, the data reported in this study suggest that some effective stress management may be undertaken by adopting selection strategies which take into consideration individual characteristics. In view of the fact that individual stress management programmes are of unproven benefit (Murphy 1986, 1988) such an approach is recommended especially for those organizations which are highly constrained in the services that must be performed.     

Job demands and work-related psychological responses among Malaysian technical workers: The moderating effects of self-efficacy

Abstract

Job design has long been found to affect the work-related psychological responses of employees, such as psychological strain, job satisfaction, and turnover intentions, but scholars have begun to question whether established theoretical relations regarding job design continue to hold given the enormous changes in the nature of work during the past two decades. It is also increasingly recognized that individual differences affect work behaviours in substantial ways, but few studies on work design have investigated these differences. We addressed these concerns with a two-wave longitudinal study among 245 technical workers at a telecommunications company in Malaysia, a country that has a collectivist culture and a high power distance between managers and subordinates. We examined the moderating effects of job control and self-efficacy on the relationships between job demands and employee responses. The results failed to support the job demands-control model, as job control variables did not moderate the impact of demands on employee work-related psychological responses. However, self-efficacy moderated their impact on psychological strain (although not on job satisfaction or turnover intentions). Our findings provide insight into the moderating effect of self-efficacy, and suggest that practitioners interested in reducing psychological strain should consider making efforts to increase self-efficacy among employees.     

Job design and levels of physical and mental strain among Australian prison officers

Abstract

Over the past 15 years much has been made of the moderating influence of job discretion and support in occupations that are perceived to be high in demands. Such an effect seems to be most prevalent when subject populations are large and heterogeneous. One aim of this study was to examine the influence of subjective perceptions of these variables on strain reactions among a group of relatively homogeneous workers such as, in the present study, prison officers (n = 274). A second aim was to extend previous research and examine the joint influence of negative affectivity and perceptions of demands, discretion, and support on mental and physical well-being. It was hypothesized that those high in negative affect would be particularly strained by jobs perceived as being demanding. The hypothesized relationship between job demands, discretion and support were found to be weak and at times inconsistent. Social support, in particular, was found to have both positive and negative consequences for different aspects of well-being. Those high in negative affect were in general found to suffer lower mental well-being. More importantly, the interactive effect of negative affectivity and job demands was found to significantly predict the majority of the dependent variables used in this study. The valences of these relationships were inconsistent and are interpreted in light of Warr's (1987) vitamin model of stress.

There are several conclusions that can be drawn from the present study. Negative affectivity appears to have a truly interactive effect with job components, job demands in particular, to influence a range of variables relating to physical and mental health as well a job-related attitudes. The nature of these effects, however, suggests a dissociation in the ways that different independent variables influence a range of indices of well-being and affect. This result requires further investigation since there are important theoretical implications which will follow if the data are replicable.

In order to examine such complex effects, in addition to the need for more longitudinal studies, it is also important that standardized measures of job components are developed so that levels of stress exposure can be equated and their impact assessed across organizational settings.

Finally, the data reported in this study suggest that some effective stress management may be undertaken by adopting selection strategies which take into consideration individual characteristics. In view of the fact that individual stress management programmes are of unproven benefit (Murphy 1986, 1988) such an approach is recommended especially for those organizations which are highly constrained in the services that must be performed.     

The distinction between work pace and working hours in the measurement of quantitative demands at work

During recent years many researchers have criticized the widely used scales on psychological job demands. For instance, they comment that in most cases different types of demand seem to be mixed in one measure. In this paper we analyse the scale on quantitative job demands in the recently developed Copenhagen Psychosocial Questionnaire (COPSOQ), with special emphasis on Differential Item Functioning (DIF). DIF refers to basic differences between groups of respondents, which may affect how they respond to questionnaire items. The data material for our study comprised a representative sample of Danish employees. The respondents were categorized into 32 specific jobs according to the International Standard Classification of Occupations (ISCO 1968). We analysed DIF with respect to the respondents' jobs with logistic regression analyses. These analyses showed that the items used in the original demand scale functioned very differently for different jobs in the population. The conclusion is that scales on quantitative demands are very sensitive to the choice of specific items. If many items on fast work pace and tempo are included in a scale, a number of blue-collar jobs will be identified as high-demand jobs. If, on the other hand, many questions on long working hours and overtime are included, the use of the scale will result in an entirely different picture. This issue has so far received little attention in occupational health psychology. The results have wide theoretical and methodological implications for research on quantitative job demands.     

The distinction between work pace and working hours in the measurement of quantitative demands at work

During recent years many researchers have criticized the widely used scales on psychological job demands. For instance, they comment that in most cases different types of demand seem to be mixed in one measure. In this paper we analyse the scale on quantitative job demands in the recently developed Copenhagen Psychosocial Questionnaire (COPSOQ), with special emphasis on Differential Item Functioning (DIF). DIF refers to basic differences between groups of respondents, which may affect how they respond to questionnaire items. The data material for our study comprised a representative sample of Danish employees. The respondents were categorized into 32 specific jobs according to the International Standard Classification of Occupations (ISCO 1968). We analysed DIF with respect to the respondents’ jobs with logistic regression analyses. These analyses showed that the items used in the original demand scale functioned very differently for different jobs in the population. The conclusion is that scales on quantitative demands are very sensitive to the choice of specific items. If many items on fast work pace and tempo are included in a scale, a number of blue-collar jobs will be identified as high-demand jobs. If, on the other hand, many questions on long working hours and overtime are included, the use of the scale will result in an entirely different picture. This issue has so far received little attention in occupational health psychology. The results have wide theoretical and methodological implications for research on quantitative job demands.     

Employee reactions to behavioural control under conditions of stress: the moderating role of self-efficacy

Extensive research conducted in the occupational stress literature has failed to provide convincing support for the stress-buffering effects of work control on employee adjustment. Drawing on research conducted in the laboratory context, it was proposed that the stress-buffering effects of work control on employee adjustment would be more marked at high, rather than low, levels of self-efficacy. In a sample of 100 customer service representatives, a significant three-way interaction among role conflict, work control and self-efficacy (measured at Time 1) was observed on (low) depersonalization (measured at Time 2). Consistent with expectations, work control reduced the negative effects of work stress on this outcome measure only for employees who perceived high levels of self-efficacy at work. In addition, there was evidence to suggest that self-efficacy moderated the main effects of work control on job satisfaction and somatic health. These findings are discussed in terms of their theoretical contribution to the job strain model, and also in relation to workplace interventions designed to improve levels of employee adjustment.     

Helping people to sort it out: The role of social support in the Job Strain Model

This paper reports three studies of occupational stress investigating the role of social support as an intervening variable in the Job Strain Model (Karasek, 1979). A computer simulated mail-sorting work environment was used to assess the effect of demands, control and social support on measures of strain, satisfaction, and perceived and actual task performance. The first experiment ( N =60) tests the basic Job Strain Model by manipulating levels of task demand and control. The second experiment ( N =120) compares high and low levels of two types of social support (informational support and emotional support) to determine whether and how they interact with extreme conditions of the Job Strain Model (high strain and low strain). The final experiment ( N =90) investigates positive and negative forms of social support (praise and criticism) in relation to extreme job strain conditions. Results show that the job strain model is consistent with the stress and performance data, although stress showed no Demand ×Control interaction. Social supports increased arousal, satisfaction and perceived performance, but did not affect stress or task performance. Moreover, contrary to buffer theories, social supports did not interact with the job strain variables. Congruence between preferred and experienced emotional support levels also predicted performance.     

Helping people to sort it out: The role of social support in the Job Strain Model

This paper reports three studies of occupational stress investigating the role of social support as an intervening variable in the Job Strain Model (Karasek, 1979). A computer simulated mail-sorting work environment was used to assess the effect of demands, control and social support on measures of strain, satisfaction, and perceived and actual task performance. The first experiment ( N =60) tests the basic Job Strain Model by manipulating levels of task demand and control. The second experiment ( N =120) compares high and low levels of two types of social support (informational support and emotional support) to determine whether and how they interact with extreme conditions of the Job Strain Model (high strain and low strain). The final experiment ( N =90) investigates positive and negative forms of social support (praise and criticism) in relation to extreme job strain conditions. Results show that the job strain model is consistent with the stress and performance data, although stress showed no Demand 2 Control interaction. Social supports increased arousal, satisfaction and perceived performance, but did not affect stress or task performance. Moreover, contrary to buffer theories, social supports did not interact with the job strain variables. Congruence between preferred and experienced emotional support levels also predicted performance.     

Chronic strain, daily work stress and pain among workers with rheumatoid arthritis: Does job stress make a bad day worse?

The structure of the job and the daily experience of work are challenges for workers with rheumatoid arthritis. Yet little is known about how these two factors interact to put workers with chronic pain at risk for worse pain on a given day. This exploratory 20 workday diary study of 27 workers with rheumatoid arthritis used hierarchical linear modelling to examine how the structure of the job and neuroticism moderate the relationship between daily undesirable work events (daily stressors), and pain reports within a day. On days with more undesirable work events compared to days with fewer events, individuals with jobs associated with job 'strain' (high demand/low control) reported greater midday pain, irrespective of neuroticism and negative mood, than workers with other combinations of demand and control. These findings demonstrate the utility of analysing fluctuating within-person relationships among pain, mood and daily work stressors within the context of the structure of the job, and helps to explain why daily work stressors result in worse health outcomes for some but not all workers with RA.     

Chronic strain,daily work stress and pain among workers with rheumatoid arthritis: Does job stress make a bad day worse?

The structure of the job and the daily experience of work are challenges for workers with rheumatoid arthritis. Yet little is known about how these two factors interact to put workers with chronic pain at risk for worse pain on a given day. This exploratory 20 workday diary study of 27 workers with rheumatoid arthritis used hierarchical linear modelling to examine how the structure of the job and neuroticism moderate the relationship between daily undesirable work events (daily stressors), and pain reports within a day. On days with more undesirable work events compared to days with fewer events, individuals with jobs associated with job ‘strain’ (high demand/low control) reported greater midday pain, irrespective of neuroticism and negative mood, than workers with other combinations of demand and control. These findings demonstrate the utility of analysing fluctuating within-person relationships among pain, mood and daily work stressors within the context of the structure of the job, and helps to explain why daily work stressors result in worse health outcomes for some but not all workers with RA.     

Employee reactions to behavioural control under conditions of stress: The moderating role of self-efficacy

Extensive research conducted in the occupational stress literature has failed to provide convincing support for the stress-buffering effects of work control on employee adjustment. Drawing on research conducted in the laboratory context, it was proposed that the stress-buffering effects of work control on employee adjustment would be more marked at high, rather than low, levels of self-efficacy. In a sample of 100 customer service representatives, a significant three-way interaction among role conflict, work control and self-efficacy (measured at Time 1) was observed on (low) depersonalization (measured at Time 2). Consistent with expectations, work control reduced the negative effects of work stress on this outcome measure only for employees who perceived high levels of self-efficacy at work. In addition, there was evidence to suggest that self-efficacy moderated the main effects of work control on job satisfaction and somatic health. These findings are discussed in terms of their theoretical contribution to the job strain model, and also in relation to workplace interventions designed to improve levels of employee adjustment.     

The importance of context specificity in work stress research: A test of the Demand-Control-Support model in academics

The Demand-Control (D-C) (Karasek, 1979) and the Demand-Control-Support (D-C-S) (Johnson & Hall, 1988; Johnson, Hall, & Theorell, 1989; Karasek & Theorell, 1990) models of work stress suggest that jobs with high demands and low control (and low support) are stressful. In line with the support in the literature for context-specificity in occupational stress research (Sparks & Cooper, 1999) and the limited and even contradictory support for interaction effects, the main aim of the present study was to examine how the D-C-S model applied in a well-defined occupational group. Using hierarchical regression analyses, and controlling for negative affect, the D-C-S model accounted for 26%, 6%, and 8% of the variance in job satisfaction, psychological distress and burnout, respectively, among 166 academics in a UK university. No two-way or three-way interactive effects were evident, but additive effects of job demands and control on psychological well-being and of job demands and support on both burnout and job satisfaction were shown, corroborating research showing that high job strain is linked to ill health and job dissatisfaction in this homogenous occupational sample. It is recommended that, in future, research includes more variables that are specific to a particular occupation.     

The Job Demands-Job Control Model and absence behaviour: results of a 3-year longitudinal study

Empirical results of earlier studies only marginally supported the relevance of Karasek's Job Demands-Job Control Model for absence behaviour. Since longitudinal studies with respect to these relations were largely lacking, a four-wave panel study was carried out using data from 1755 male employees of a technical maintenance firm in the public sector. Job demands, job control, physical working conditions, and the employee's age, education, and health were measured in one year and absenteeism in the same year and in the next 3 years. Data were analysed with linear regression and Poisson regression techniques. The Poisson regression technique was superior to the linear regression technique in explaining absence. Age, health and prior absence were the best predictors of later absence behaviour. With respect to the Job Demands-Job Control Model, the main findings of the study were (1) that job control was significantly associated with a low number of simultaneous and later absence days, and (2) that, contrary to expectations, job demands were also related to a low number of simultaneous and later absence days. These results hold when age, health, education, prior absence, and working conditions are controlled for. Job control and job demands did not predict later absence frequency. In the discussion it is suggested that a high level of job demands may not only be harmful for the well-being of employees but also work as 'a pressure to attend'.