Methodological and conceptual issues in studying effort-reward fit

Purpose

Research on effort-reward “imbalance” (ERI) has gained popularity in the occupational health literature, and authors typically use effort-reward ratios (ERRs) to study this phenomenon. This article provides a methodological and theoretical critique of this literature and suggestions on how future research can better study joint effects of efforts and reward.

Design/methodology/approach

The authors conducted a simulation study, analyzed panel data and surveyed the literature on the theoretical and methodological basis of the “imbalance” concept.

Findings

The simulation study indicates that under many conditions the ERR captures main effects of effort and reward and that effects also depend on the scaling of the variables. The panel data showed that when main effects and the interactions of effort and reward are entered simultaneously in a regression predicting mental and physical health, the significant effect of the ERRs disappears. The literature review reveals that psychological theories include more elaborate theoretical ideas on joint effects of effort and reward.

Research limitations/implications

The results suggest that moderated multiple regression analyses are better suited to detect a misfit between effort and reward than ERRs. The authors also suggest to use the term effort-reward fit in future research.

Originality/value

Methodologically and conceptually the authors showed that the ERR is not an appropriate approach because it confuses main effects with interaction effects. Furthermore, the concept of ERI is better substituted by a broader conceptualization of effort-reward fit that can be integrated with the existing literature on person-environment fit. Recommendations for future research are provided.

Labour Market Status and Well-Being in the Context of Return to Work After Vocational Rehabilitation in Germany

INTRODUCTION

Although there is much empirical evidence for a given relationship between health and labour market status (LMS), the following study focuses on a group for which little is known in the German context: people with disabilities in vocational rehabilitation for the purpose of re-integration into the labour market. In this specific context, the article analyses how a change in LMS affects physical, mental and general health.

METHODS

Using a panel survey, 857 people with disabilities in vocational rehabilitation and their subjective health condition were observed between 2008 and 2010. To reduce bias due to unobserved heterogeneity, fixed-effects panel regression is applied.

RESULTS

Results show that a move from non-employment to employment positively affects-particularly general-subjective health. In addition to LMS, the level of occupational limitation due to disability appears to be of particular relevance in estimating health. Interacting both the level of occupational limitation and LMS reveals that non-employed people reporting serious occupational limitation due to their disability have the worst subjective health across all aspects. However, people in employment experiencing similarly serious limitations due to their disability do not differ much from this group. These may be regarded as having taken up disability-inappropriate employment.

CONCLUSION

The results suggest that re-integration into employment particularly improves several health aspects if rehabilitants are integrated in an occupational environment where disability does not present an occupational limitation. Thus, placement in disability-appropriate employment needs to be particularly encouraged.

Psychosocial work factors, blood pressure and psychological strain in male bus operators

The research aim was to predict the bus operators' blood pressure (BP) and psychological strain using a combination of the Job-Demand Control (JDC) and Effort-Reward Imbalance (ERI) models. The study was conducted with a sample of 139 bus operators in the city of Bogotá (Colombia), who answered a questionnaire that included the Job Content Questionnaire (JCQ), the ERI Questionnaire, and the General Health Questionnaire (GHQ). Four consecutive BP readings taken in the workplace were averaged to calculate an estimation of the bus operators' BP. By conducting multiple linear regressions it was found that, taken together, JDC and ERI models explain 10% (F(11,139)=2,502; p=0.00) of systolic BP variance, and 34% (F(6,139)=8,638; p=0.00) of psychological strain variance. These results suggest that the JDC and ERI predictors provide complementary information which increases the probability of accurately model the bus operators' health.

Musculoskeletal pain and effort-reward imbalance--a systematic review

Background

Musculoskeletal pain may be triggered by physical strains and psychosocial risk factors. The effort-reward imbalance model (ERI model) is a stress model which measures psychosocial factors in the working world. The question is whether workers with an effort-reward imbalance report musculoskeletal pain more frequently than those with no effort-reward imbalance. A systematic review using a best evidence synthesis approach was conducted to answer this question.

Methods

A literature search was conducted for the period from 1996 to 2012, using three databases (Pubmed, Embase and PsycINFO). The research criteria related to psychosocial, work-related stress as per the ERI model and to musculoskeletal pain. A quality score was developed using various quality criteria to assess the standard of the studies. The level of evidence was graded as in (Am J Ind Med 39:180–193, 2001).

Results

After applying the inclusion criteria, a total of 19 studies were included in the review: 15 cross-sectional studies, three prospective studies and one case–control study. 74% of all studies exhibited good methodological quality, 53% collected data using the original ERI questionnaire, and in 42% of the studies, there was adequate control for physical working conditions. Furthermore, different cut-off points were used to classify exposed and non-exposed individuals. On the basis of 13 studies with a positive, statistically significant association, a moderate level of evidence was inferred for the association between effort-reward imbalance and musculoskeletal pain. The evidence for a role of over-commitment and for its interaction with effort-reward imbalance was rated as inconclusive - on the basis of eight and five studies, respectively.

Conclusions

On the basis of the available evidence, no reliable conclusion may be drawn about any association between the psychosocial factors ascertained using the ERI model and musculoskeletal pain. Before a reliable statement can be made on the association between ERI and musculoskeletal pain, additional longitudinal studies must be performed - with a standardised method for recording and classifying exposure, as well as control of physical confounders. Appropriate preventive measures can then be specified.

Job strain, effort-reward imbalance and neck, shoulder and wrist symptoms among Chinese workers

The purpose of this study was to examine the association between psychosocial job stress (by the Job Control-Demand (JCD) model and Effort-Reward imbalance (ERI) model) and musculoskeletal (MS) symptoms among workers in China. Overall, 3,632 male and 1,706 female workers from 13 factories/companies participated in this study. Perceived job stress was evaluated by the Chinese version of the Job Content Questionnaire (JCQ) and ERI Questionnaire. Neck, shoulder and wrist symptoms were assessed by self-report during the past year. Workers reporting high job demands and low job control or high effort and low rewards had moderately increased risk for all MS symptoms. Odds ratios (ORs) were higher in workers reporting both high effort and low rewards. The combination of high physical job demands with low job control showed significant associations with MS symptoms. The effects of psychological demands on symptoms in women, effort and effort-reward imbalance on symptoms among both genders were increased as the number of regions with symptoms increased. These results suggest that high job strain and ERI are associated with neck, shoulder and wrist symptoms in Chinese factory workers independent of individual factors, physical factors, and other psychological variables.

Do Not Go Gentle Into That Good Night: The Effect of Retirement on Subsequent Mortality of U.S. Supreme Court Justices, 1801–2006

Mortality hazard and length of time until death are widely used as health outcome measures and are themselves of fundamental demographic interest. Considerable research has asked whether labor force retirement reduces subsequent health and its mortality measures. Previous studies have reported positive, negative, and null effects of retirement on subsequent longevity and mortality hazard, but inconsistent findings are difficult to resolve because (1) nearly all data confound retirement with unemployment of older workers, and often, (2) endogeneity bias is rarely addressed analytically. To avoid these problems, albeit at loss of generalizability to the entire labor force, I examine data from an exceptional subgroup that is of interest in its own right: U.S. Supreme Court justices of 1801–2006. Using discrete-time event history methods, I estimate retirement effects on mortality hazard and years-left-alive. Some substantive and methodological considerations suggest models that specify endogenous effects estimated by instrumental variables (IV) probit, IV Tobit, and IV regression methods. Other considerations suggest estimation by endogenous switching (ES) probit and ES regression. Estimates by all these methods are consistent with the hypothesis that, on average, retirement decreases health, as indicated by elevated mortality hazard and diminished years-left-alive. These findings may apply to other occupational groups characterized by high levels of work autonomy, job satisfaction, and financial security.

Effort-reward imbalance and depression in Japanese medical residents

The effort-reward imbalance is an important psychosocial factor which is related to poor health among employees. However, there are few studies that have evaluated effort-reward imbalance among medical residents. The present study was done to determine the association between psychosocial factors at work as defined by the effort-reward imbalance model and depression among Japanese medical residents. We distributed a questionnaire to 227 medical residents at 16 teaching hospitals in Japan at the end of August 2005. We asked participants to answer questions which included demographic information, depressive symptoms, effort-reward imbalance, over-commitment and social support. Depression was evaluated using the Japanese version of the Center for Epidemiologic Studies-Depression (CES-D) scale. The effort-reward imbalance and over-commitment were assessed by the Effort-Reward Imbalance (ERI) questionnaire which Siegrist developed. Social support was determined on a visual analog scale. Logistic regression analysis was performed to determine the associations between effort-reward imbalance and depressive symptoms. Depressive symptoms were found in 35 (29.2%) 1st-year residents and 21 (27.6%) 2nd-year residents. The effort-reward ratio >1 (OR, 8.83; 95% CI, 2.87-27.12) and low social support score (OR, 2.77, 95% CI, 1.36-5.64) were associated with depressive symptoms among medical residents. Effort-reward imbalance was independently related to depression among Japanese medical residents. The present study suggests that balancing between effort and reward at work is important for medical residents' mental health.

Psychosocial work environment and well-being: a cross-sectional study at a thermal power plant in China

To investigate the effects of the job demand-control (DC) model and the effort-reward imbalance (ERI) model on worker's well-being, self-reports for psychosocial work conditions and well-being were made by a sample of 878 workers at a thermal power plant in China using the main dimensions of DC and ERI questionnaires. Logistic regression analyses were employed controlling for age, gender, and educational level, and negative and positive affection among others. Workers reporting high job demands and low job control or high efforts and low rewards had elevated risks of job dissatisfaction, psychosomatic complaints and depressive symptoms. Odds ratios were generally higher in workers reporting both high efforts and low rewards. Furthermore, low reward proved to be a stronger predictor of poor well-being when both job stress models were simultaneously adjusted. To some extent, interaction effects were found for social support, but no interaction effects were found for overcommitment. The findings indicate independent effects of both the DC model and the ERI model on well-being. Future work should explore the combined effects of these two models of psychosocial stress at work on health more thoroughly.

Psychosocial work stress is associated with poor self-rated health in Danish nurses: a test of the effort-reward imbalance model

Nursing staff are exposed to stressful work load which in turn is associated with poor physical and psychological health, sickness absence and job exit. The effort-reward imbalance (ERI) model is a validated approach to measure chronic psychosocial work stress by identifying nonreciprocity between occupational efforts spent and rewards received, and has been found to predict poor health. The aim of this cross-sectional study (n = 367 nurses and nurses aides) was first to test the psychometric properties of the Danish questionnaire measuring ERI, and secondly to analyse whether psychosocial work stress is associated with six indicators of poor self-rated health. Results derived from confirmatory factor analysis indicate satisfying psychometric properties. Elevated risks of poor self-rated health (odds ratios varying from 1.92 to 4.76) are observed in nursing staff characterized by high effort in combination with low reward. Effects are enhanced in those respondents who additionally exhibit a high level of work-related overcommitment. In conclusion, despite methodological limitations, this study contributes to the validation of the ERI questionnaire in Danish language. Furthermore, by documenting associations with poor self-rated health, it supports efforts of theory-guided prevention of work stress in health care professions.

Effort–reward imbalance, sleep disturbances and fatigue

OBJECTIVES

The objective of this study was to investigate the validity of the effort-reward imbalance (ERI) model in relation to disturbed sleep and fatigue.

METHODS

The study population derived from a subset of the WOLF (WOrk, Lipids, Fibrinogen) cohort study of cardiovascular risk in a working population who replied to the ERI-questionnaire comprising 789 men and 214 women. Cox regression analysis was used to calculate the prevalence ratio (PR) for sleep disorders and fatigue in relation to the components of ERI.

RESULTS

As sleep disturbances and fatigue, based on literature, were defined to be represented by the uppermost quintile, 14% of the men and 23% of the women were affected by sleep disturbances while 14 and 26%, respectively, were affected by fatigue. Higher levels of exposure for the ERI components were associated with increased prevalence of sleep disturbances and fatigue. For men, the strongest association was seen between high overcommitment and fatigue (PR 5.77, 95% confidence interval 2.89-11.5). For women, high effort and sleep disturbances (PR 4.04, CI 1.53-10.7), high effort/reward ratio and sleep disturbances (PR 4.13, CI 1.62-10.5), and between low reward and fatigue (PR 4.36, CI 1.79-10.6) yielded the most obvious associations.

CONCLUSIONS

The present study adds sleep disturbances and fatigue to the list of adverse consequences of effort-reward imbalance.

Reviewing the effort–reward imbalance model: drawing up the balance of 45 empirical studies

The present paper provides a review of 45 studies on the Effort-Reward Imbalance (ERI) Model published from 1986 to 2003 (inclusive). In 1986, the ERI Model was introduced by Siegrist et al. (Biological and Psychological Factors in Cardiovascular Disease, Springer, Berlin, 1986, pp. 104-126; Social Science & Medicine 22 (1986) 247). The central tenet of the ERI Model is that an imbalance between (high) efforts and (low) rewards leads to (sustained) strain reactions. Besides efforts and rewards, overcommitment (i.e., a personality characteristic) is a crucial aspect of the model. Essentially, the ERI Model contains three main assumptions, which could be labeled as (1) the extrinsic ERI hypothesis: high efforts in combination with low rewards increase the risk of poor health, (2) the intrinsic overcommitment hypothesis: a high level of overcommitment may increase the risk of poor health, and (3) the interaction hypothesis: employees reporting an extrinsic ERI and a high level of overcommitment have an even higher risk of poor health. The review showed that the extrinsic ERI hypothesis has gained considerable empirical support. Results for overcommitment remain inconsistent and the moderating effect of overcommitment on the relation between ERI and employee health has been scarcely examined. Based on these review results suggestions for future research are proposed.

Gender differences in the relationship of partner's social class to behavioural risk factors and social support in the Whitehall II study

In most countries health inequality in women appears to be greater when their socio-economic position is measured according to the occupation of male partners or spouses than the women's own occupations. Very few studies show social gradients in men's health according to the occupation of their female partners. This paper aims to explore the reasons for the differences in social inequality in cardiovascular disease between men and women by analysing the associations between own or spouses (or partners) socio-economic position and a set of risk factors for prevalent chronic diseases. Study participants were married or cohabiting London based civil servants included in the Whitehall II study. Socio-economic position of study participants was measured according to civil service grade; socio-economic position of the spouses and partners according to the Registrar General's social class schema. Risk factors were smoking, diet, exercise, alcohol consumption, and measures of social support. In no case was risk factor exposure more affected by the socio-economic position of a female partner than that of a male study participant. Wives' social class membership made no difference at all to the likelihood that male Whitehall participants were smokers, or took little exercise. Female participants' exercise and particularly smoking habit was, in contrast, related to their spouse's social class independently of their own grade of employment. Diet quality was affected equally by the socio-economic position of both male and female partners. Unlike the behavioural risk factors, the degree of social support reported by women participants was in general not strongly negatively affected by their husband or partner being in a less advantaged social class. However, non-employment in the husband or partner was associated with relatively lower levels of positive, and higher negative social support, while men with non-working wives or partners were unaffected. Studying gender differences in health inequality highlights some of the problems in health inequality research more broadly. We are brought face to face with the fact that the development of conceptual models that can be applied consistently to aetiology in both men and women are still at an early stage of development. Closer attention is needed to the different processes behind material power and 'emotional power' within the household when investigating gender differences in health and risk factors.

Effort-reward imbalance model and self-reported health: cross-sectional and prospective findings from the GAZEL cohort

Psychosocial factors at work have been found to be significant contributors to health, especially cardiovascular health. This study is aimed at exploring the relationship between psychosocial factors at work as defined by the effort-reward imbalance (ERI) model and self-reported health, using alternative formulations of this model, and comparing cross-sectional and prospective analyses for a large occupational cohort of men and women. The French version of the ERI model was used to measure the three scales of effort, reward, and overcommitment. Self-reported health was used as health outcome. Covariates included chronic diseases, frequent depressive symptoms, and personal, occupational, and behavioural factors. The cross-sectional and prospective analyses concerned, respectively, 10175 and 6286 workers. Men and women were analysed separately. Cross-sectional analysis revealed that ERI was significantly associated with self-reported health whatever the formulation used (ratio over one, quartiles, continuous ratio, or log-transformed ratio) for both genders. When effort and reward were studied as two separate variables, reward was a significant risk factor for both genders, whereas effort was for men only. Overcommitment was also found to be a risk factor for self-reported health for both sex. Prospective analysis showed that ERI was a significant predictor of poor self-reported health for men and women for two formulations (continuous ratio and log-transformed ratio). For both genders, effort did not predict self-reported health, but reward did. Overcommitment was predictive of poor self-reported health for men only. Our results highlighted the predictive effects of the ERI model on self-reported health in a 1-year follow-up study. They urged to explore various formulations of the ERI model. They also underlined the need for longitudinal study design and separate analyses for men and women in the field of psychosocial factors at work.

The psychosocial work environment and musculoskeletal disorders: design of a comprehensive interviewer-administered questionnaire

BACKGROUND

Psychosocial working conditions are likely to contribute to work-related musculoskeletal disorders (WRMSDs), but a lack of standardized measurement tools reflects both the theoretical and methodological limitations of current research.

METHODS

An interdisciplinary team including biomedical, behavioral, and social science researchers used an iterative process to adapt existing instruments for an interviewer-administered questionnaire assessing psychosocial workplace exposure related to musculoskeletal disorders.

RESULTS

The resulting questionnaire included measures of psychosocial workplace factors based on two theoretical models (the demand-control-support and the effort-reward imbalance models), supplemented by the additional constructs of "emotional demands," and "experiences of discrimination." Other psychosocial and physical measures selected for questionnaire inclusion address physical workload, sociodemographic and anthropometric characteristics, social relations and life events, health behaviors, and physical and psychological health.

CONCLUSION

Using an interdisciplinary approach facilitated the development of a comprehensive questionnaire inclusive of key measures of psychosocial factors that may play a role in the complex mechanisms leading to WRMSDs.

Differential economic stability and psychosocial stress at work: associations with psychosomatic complaints and absenteeism

Stressful working conditions are well known to have a negative impact on the worker's health. We investigated this association in a Belgian study with a psychosocial health perspective, including individual work characteristics as well as firms' features. These data come from the first measure of the Somstress study. This is a 4 year project, initiated in 1999 and conducted in four different firms. The objective of this article is to investigate the relationships between stress, working conditions and absenteeism, self-reported health and psychosomatic complaints. Firms were selected according to their degree of structural environment and job stability. Among the four work sites, one can be considered as stable, one unstable and the remaining ones in an in-between situation. Stress is generally measured according to one of the following models: the job demands control model (Karasek) and the effort-reward imbalance model (Siegrist). We used here both models, along with the social support at work (Karasek) and overcommitment (Siegrist). Sex, age and education are important health determinants. After adjustment for those three variables and additionally for the work instability, it appeared that poor health outcomes (measured by the self-rated health, depression (SCL-90), anxiety (SCL-90), somatisation (SCL-90), chronic fatigue (Vercoulen) and reported absenteeism) are mainly associated with a low control, low social support at work, high overcommitment and high level of imbalance. Inversely, job demands do not make any significant contribution in the logistic regression models for the above-mentioned health outcomes.

[Measuring psychosocial stress at work in Spanish hospital's personnel. Psychometric properties of the Spanish version of Effort-Reward Imbalance model]

BACKGROUND AND OBJECTIVE

Two main models are currently used to evaluate the psychosocial factors at work: the Demand-Control (or job strain) model developed by Karasek and the Effort-Reward Imbalance model, developed by Siegrist. A Spanish version of the first model has been validated, yet so far no validated Spanish version of the second model is available. The objective of this study was to explore the psychometric properties of the Spanish version of the Effort-Reward Imbalance model in terms of internal consistency, factorial validity, and discriminate validity.

SUBJECTS AND METHODS

A cross-sectional study on a representative sample of 298 workers of the Spanish public hospital San Agustin in Asturias was performed. The Spanish version of Effort-Reward Imbalance Questionnaire (23 items) was obtained by a standard forward/backward translation procedure, and the information was gathered by a self-administered application. Exploratory factor analysis were performed to test the dimensional structure of the theoretical model. Cronbach's alpha coefficient was calculated to estimate the internal consistency reliability. Information on discriminate validity is given for sex, age and education. Differences were calculated with the t-test for two independent samples or ANOVA, respectively.

RESULTS

Internal consistency was satisfactory for the two scales (reward and intrinsic effort) and Cronbach's Alpha coefficients higher than 0.80 were observed. The internal consistency for the scale of extrinsic effort was lower (alpha = 0.63). A three-factor solution was retained for the factor analysis of reward as expected, and these dimensions were interpreted as a) esteem, b) job promotion and salary and c) job instability. A one-factor solution was retained for the factor analysis of intrinsic effort. The factor analysis of the scale of extrinsic effort did not support the expected one-dimension structure. The analysis of discriminate validity displayed significant associations between measures of Effort-Reward Imbalance and the variables of sex, age and education level.

CONCLUSIONS

This study is the first one supporting satisfactory psychometric properties of the Spanish version of the Effort-Reward Imbalance model. However, the factorial validity of the extrinsic effort could be questioned.

Responsiveness of measures in the effort-reward imbalance questionnaire to organizational changes: a validation study

OBJECTIVE

To examine the responsiveness of measures adopted in the effort-reward imbalance (ERI) questionnaire to organizational changes.

METHOD

For the employees who had been affected by restructuring of their company due to the economic hardship, two consecutive questionnaire surveys were conducted over a specific period. A total of 544 full-time employees responded to both surveys. Changes in four summary measures from the situation-specific model component and the person-specific component, and items/subscales that constitute the questionnaire were evaluated.

RESULTS

The summary measures on psychological deterioration in the total study population. The deterioration was prevalent in those employees who had presumably experienced the effects of stressful organizational changes related to the restructuring, while improvement in the summary measures was observed for those employees who were promoted during the period. On the whole, the measures for the items of the situation-specific component and subscales for the personal component changed in the expected direction. With regard to ERI, potentially stronger effects of multiple organizational changes on employees were indicated.

CONCLUSION

Measurements of ERI at work are valid in terms of responsiveness to organizational changes.

Job strain, effort-reward imbalance and employee well-being: a large-scale cross-sectional study

This study investigated the effects of the Job Demand-Control (JD-C) Model and the Effort-Reward Imbalance (ERI) Model on employee well-being. A cross-sectional survey was conducted comprising a large representative sample of 11,636 employed Dutch men and women. Logistic regression analyses were used. Controlling for job sector, demographic characteristics (including educational level) and managerial position, employees reporting high job demands (i.e. psychological and physical demands) and low job control had elevated risks of emotional exhaustion, psychosomatic and physical health complaints and job dissatisfaction (odds ratios ranged from 2.89 to 10.94). Odds ratios were generally higher in employees reporting both high (psychological and physical) efforts and low rewards (i.e. poor salary, job insecurity and low work support): they ranged from 3.23 to 15.43. Furthermore, overcommitted people had higher risks of poor well-being due to a high effort-low reward mismatch (ORs: 3.57-20.81) than their less committed counterparts (ORs: 3.01-12.71). Finally, high efforts and low occupational rewards were stronger predictors of poor well-being than low job control when both job stress models were simultaneously adjusted. In conclusion, our findings show independent cumulative effects of both the JD-C Model and the ERI Model on employee well-being and are not significantly different in men and women as well as in young and old people. In particular, high (psychological and physical) efforts and low rewards adversely affected employee well-being. Preliminary findings also indicate excess risks of poor well-being in overcommitted persons suffering from high cost--low gain conditions at work.

Effort-reward imbalance and burnout among nurses

This study among a sample of 204 German nurses tested the hypothesis that an imbalance of high extrinsic efforts spent (i.e. job demands) and low extrinsic rewards obtained (e.g. poor promotion prospects) are associated with the burnout syndrome: the depletion of nurses' emotional resources. The results of a series of analyses of variances confirmed this hypothesis, by showing that those nurses who experienced an effort-reward imbalance (ERI) reported higher levels on two of the three core dimensions of burnout (i.e. emotional exhaustion and depersonalization) than those who did not experience such an imbalance. Moreover - as additionally hypothesized - significant interaction effects indicated that burnout (i.e. emotional exhaustion and reduced personal accomplishment) was particularly prevalent among those nurses who experienced ERI and put relatively high intrinsic effort into their jobs, as reflected by their strong tendency to be personally in control over job conditions.