The job content questionnaire in various occupational contexts: applying a latent class model.

OBJECTIVE: To evaluate Job Content Questionnaire(JCQ) performance using the latent class model. METHODS: We analysed cross-sectional studies conducted in Brazil and examined three occupational categories: petroleum industry workers (n=489), teachers (n=4392) and primary healthcare workers (3078)and 1552 urban workers from a representative sample of the city of Feira de Santana in Bahia, Brazil. An appropriate number of latent classes was extracted and described each occupational category using latent class analysis, a multivariate method that evaluates constructs and takes into accountthe latent characteristics underlying the structure of measurement scales. The conditional probabilities of workers belonging to each class were then analysed graphically. RESULTS: Initially, the latent class analysis extracted four classes corresponding to the four job types (active, passive, low strain and high strain) proposed by the Job-Strain model (JSM) and operationalised by the JCQ. However, after taking into consideration the adequacy criteria to evaluate the number of extracted classes, three classes (active, low strain and high strain) were extracted from the studies of urban workers and teachers and four classes (active, passive, low strain and high strain) from the study of primary healthcare and petroleum industry workers. CONCLUSION: The four job types proposed by the JSM were identified among primary healthcare and petroleum industry workers-groups with relatively high levels of skill discretion and decision authority. Three job types were identified for teachers and urban workers; however, passive job situations were not found within these groups. The latent class analysis enabled us to describe the conditional standard responses of the job types proposed by the model, particularly in relation to active jobs and high and low strain situations.

Insomnia increases risk for cardiovascular events in women and in men with low socioeconomic status: a longitudinal, register-based study.

OBJECTIVES: Insomnia and short and long sleep durations have all been linked to cardiovascular disease. Male gender and low socioeconomic status are also related to cardiovascular disease, but it is unclear whether these two factors modify the impact of poor sleep on cardiovascular disease incidence. METHODS: Participants (5875 men and 7742 women ages 45 to 64 with no history of cardiovascular disease from the general population of Malmö, Sweden; participation rate 41%) were enrolled from 1992 to 1994 and followed until 2005 or until the first cardiovascular event (defined as myocardial infarction, stroke, or death due to ischemic heart disease), as recorded by official registers. Baseline blood pressure, BMI, and inquiry data concerning psychosocial circumstances and self-reported sleep habits were compared with hazard ratios (HRs) of cardiovascular events. RESULTS: Affirming 'moderate' or 'considerable' problems with at least one out of the four insomnia symptoms was associated with cardiovascular event in women (fully-adjusted HR 1.4 [95% CI 1.2-1.6] and population attributable fraction 17.3%). The same was true of men with past or present manual occupation (HR 1.3 [95% CI 1.1-1.6] and population attributable fraction 11.8%). The HRs increased further in women where insomnia symptoms were combined with short or long sleep duration. CONCLUSIONS: Insomnia is a significant public health problem with implications for cardiovascular disease incidence. Taking gender and socioeconomic status into account is a worthwhile approach in research on sleep and cardiovascular disease outcomes.

Insomnia symptoms, sleep duration, and disability pensions: a prospective study of Swedish workers.

BACKGROUND: Previous studies have found insomnia and long sleep duration to be independently associated with subsequent disability pension (DP). However, the issue of a possible gender-based pattern in this context has received little attention. PURPOSE: This study aims to assess the impact of insomnia symptoms and sleep duration on the DP rates among Swedish women and men during a 12-year follow-up period. METHOD: The participants, from the general population of Malmö, Sweden, were enrolled from 1992 to 1994 (n = 4,319; participation rate 41 %), aged 45-64, healthy, and employed ≥30 h per week. Baseline inquiry data concerning psychosocial circumstances and self-reported sleep habits were compared with official register-based DP rates. RESULTS: Five hundred and nine persons were granted a DP. Insomnia symptoms, affirmed by 33 % of the men and 41 % of the women, were associated with receiving a DP; the hazard ratios in the fully adjusted model were 1.4 for both men [95 % confidence interval (CI) 1.1, 1.9] and women (95 % CI 1.1, 1.7). The fully adjusted hazard ratio for women sleeping ≥9 h was 7.8 (95 % CI 3.7, 16.6) for DP due to a mental disorder. In the age-adjusted analyses, the sub-domain "difficulties falling asleep" was related to DP due to mental disorders in men and DP due to cardiovascular diseases in women. CONCLUSION: The findings suggest that preventing and treating insomnia symptoms could reduce DP and that disease mechanisms linking sleep disturbances to DP may differ by gender.

Factor structure and longitudinal measurement invariance of the demand control support model: an evidence from the Swedish Longitudinal Occupational Survey of Health (SLOSH).

OBJECTIVES: To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ), using the Swedish Longitudinal Occupational Survey of Health (SLOSH). METHODS: A confirmatory factor analysis (CFA) and multi-group confirmatory factor analysis (MGCFA) models within the framework of structural equation modeling (SEM) have been used to examine the factor structure and invariance across time. RESULTS: Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42) between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68). The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. CONCLUSION: Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes.

Associations of job strain and lifestyle risk factors with risk of coronary artery disease: a meta-analysis of individual participant data.

BACKGROUND: It is unclear whether a healthy lifestyle mitigates the adverse effects of job strain on coronary artery disease. We examined the associations of job strain and lifestyle risk factors with the risk of coronary artery disease. METHODS: We pooled individual-level data from 7 cohort studies comprising 102 128 men and women who were free of existing coronary artery disease at baseline (1985-2000). Questionnaires were used to measure job strain (yes v. no) and 4 lifestyle risk factors: current smoking, physical inactivity, heavy drinking and obesity. We grouped participants into 3 lifestyle categories: healthy (no lifestyle risk factors), moderately unhealthy (1 risk factor) and unhealthy (2-4 risk factors). The primary outcome was incident coronary artery disease (defined as first nonfatal myocardial infarction or cardiac-related death). RESULTS: There were 1086 incident events in 743,948 person-years at risk during a mean follow-up of 7.3 years. The risk of coronary artery disease among people who had an unhealthy lifestyle compared with those who had a healthy lifestyle (hazard ratio [HR] 2.55, 95% confidence interval [CI] 2.18-2.98; population attributable risk 26.4%) was higher than the risk among participants who had job strain compared with those who had no job strain (HR 1.25, 95% CI 1.06-1.47; population attributable risk 3.8%). The 10-year incidence of coronary artery disease among participants with job strain and a healthy lifestyle (14.7 per 1000) was 53% lower than the incidence among those with job strain and an unhealthy lifestyle (31.2 per 1000). INTERPRETATION: The risk of coronary artery disease was highest among participants who reported job strain and an unhealthy lifestyle; those with job strain and a healthy lifestyle had half the rate of disease. A healthy lifestyle may substantially reduce disease risk among people with job strain.

Can high psychological job demands, low decision latitude, and high job strain predict disability pensions? A 12-year follow-up of middle-aged Swedish workers.

OBJECTIVES: The aim of this study was to investigate whether job strain, psychological demands, and decision latitude are independent determinants of disability pension rates over a 12-year follow-up period. METHODS: We studied 3,181 men and 3,359 women, all middle-aged and working at least 30 h per week, recruited from the general population of Malmö, Sweden, in 1992. The participation rate was 41 %. Baseline data include sociodemographics, the Job Content Questionnaire, lifestyle, and health-related variables. Disability pension information was obtained through record linkage from the National Health Insurance Register. RESULTS: Nearly 20 % of the women and 15 % of the men were granted a disability pension during the follow-up period. The highest quartile of psychological job demands and the lowest quartile of decision latitude were associated with disability pensions when controlling for age, socioeconomic position, and health risk behaviours. In the final model, with adjustment also for health indicators and stress from outside the workplace, the hazard ratios for high strain jobs (i.e. high psychological demands in combination with low decision latitude) were 1.5 in men (95 % CI, 1.04-2.0) and 1.7 in women (95 % CI, 1.3-2.2). Stratifying for health at baseline showed that high strain tended to affect healthy but not unhealthy men, while this pattern was reversed in women. CONCLUSIONS: High psychological demands, low decision latitude, and job strain were all confirmed as independent risk factors for subsequent disability pensions. In order to increase chances of individuals remaining in the work force, interventions against these adverse psychosocial factors appear worthwhile.

The perception of work stressors is related to reduced parasympathetic activity.

PURPOSE: The aim was to examine the perception of work stressors in relation to ambulatory measures of heart rate variability (HRV). METHODS: Results are based on a sample of 653 healthy male workers aged 40-55 from the Belgian Physical Fitness Study conducted in 1976-1978. Data were collected by means of self-administered questionnaires and bio-clinical examinations. An index of physical and psychosocial work stressors containing five items was constructed based on the job stress questionnaire. Data on HRV were collected by means of 24-h ambulatory ECG recordings on a working day. Both time and frequency domain measures of HRV were calculated. Associations between work stressors and HRV measures were assessed by means of correlations, multiple linear regression analysis and analysis of (co)variance. RESULTS: The work stressor index was significantly associated with lower pNN50 (the percentage of differences between adjacent normal RR intervals > 50 ms), lower high frequency power and a higher ratio of low frequency over high frequency power. Very similar results were obtained after adjusting for age, language, occupation, smoking, body mass index, total cholesterol, systolic blood pressure and leisure time physical activity. No significant associations were found with SDNN (the standard deviation of all normal RR intervals) and low frequency power. CONCLUSIONS: The perception of work stressors was related to reduced parasympathetic activity in a sample of 653 healthy male workers. These findings support the idea that particularly the parasympathetic component of the autonomic nervous system is related to work stress.

Synergistic interaction effect between job control and social support at work on general psychological distress.

PURPOSE: Little is known about the interaction between job control and social support at work on common mental disorders. To examine whether there is a synergistic interaction effect between job control and social support at work on general psychological distress and whether it differs by the level of job demands. METHODS: About 1,940 male and female workers from the Malmö Shoulder and Neck Study were chosen for this cross-sectional study. Job control, social support at work, and job demands were measured by the Swedish version of the Job Content Questionnaire, and general psychological distress was assessed by the General Health Questionnaire. RESULTS: A significant excessive risk increase for general psychological distress was observed when workers had both low job control and low social support at work in both men and women. The synergistic effect was stronger in women, when job demands were low (Rothman's synergy index was 2.16 vs. 1.51 when job demands were high). However, in male workers, while a strong synergistic effect between job control and social support at work was found when job demands were low (synergy index was 9.25), there was an antagonistic effect when job demands were high (synergy index was 0.52). CONCLUSIONS: There was a synergistic interaction effect between job control and social support at work on general psychological distress, but the synergistic effect or its effect size differed by the level of job demands and gender. An atomic, additive approach to the risk assessment of the psychosocial work characteristics on common mental disorders could be misleading or lead to a risk underestimation.

Psychosocial working conditions and exhaustion in a working population sample of Swedish middle-aged men and women.

BACKGROUND: Exhaustion is a concept of interest for both occupational health research and stress-disease theory research. The aim of the present study was to explore associations between chronic stressors, in terms of psychosocial working conditions, and exhaustion in a Swedish middle-aged population sample. METHODS: A vocationally active population sample of the Malmö Shoulder and Neck Study cohort, comprising 2555 men and 2466 women between 45 and 64 years of age, was used. Psychosocial working conditions, assessed by means of the demand-control-support model, were measured longitudinally with a 1-year interval. Exhaustion was assessed by the SF-36 vitality scale and measured at follow-up, yielding a cross-sectional study design. RESULTS: Exhaustion was twice as common in women as in men. High psychological job demands, low job control and low job support were independently associated with exhaustion in both men and women. These associations remained after controlling for a variety of potential confounders and mediators, including socio-demographic factors, lifestyle factors, musculoskeletal pain, disease, other work-related factors (including physical workload) and non-work-related factors. High demands in combination with low control (job strain), and job strain combined with low job support (iso-strain), increased the risk for exhaustion. CONCLUSION: Psychosocial working conditions seem to contribute to exhaustion in middle-aged men and women. Future research should include exploration of exhaustion as a possible mediator between work stress and disease, as well as exploration of other chronic stressors, including non-work-related stressors, regarding their effects on exhaustion in men and women.

Reduced vagal cardiac control variance in exhausted and high strain job subjects.

OBJECTIVES: This paper has two primary objectives. First, the paper proposes methodological strategies for analyzing multiscale vagal cardiac control based on the Stress Disequilibrium Theory (SDT) using high frequency power of heart rate variability (HFP) and short term variance of HFP. Second, the paper provides evidence of reduced vagal cardiac control range and variability in high strain job and exhausted subjects. MATERIALS AND METHODS: Job Strain was measured using the Job Content Questionnaire, 8/day diary reports, and a nationally standardized occupational code linkage in 36 healthy mid-aged males with varying strain jobs. Subjects were Holter-monitored for 48 hours, including a work and rest day. Subjects responded to questions on a daily diary as well as on the Job Content Questionnaire to test for exhaustion as a dichotomous state variable. Vagal cardiac control was measured by components of electrocardiograph: heart rate variability based measures of high frequency power (HFP). We assessed range of vagal cardiac control using extreme value analysis (data in upper tail); and short term vagal variability using Poincaré plots of HFP. Comparisons were made between high (N = 10) and low job strain (N = 22) jobs. Furthermore, subjects categorized as exhausted (N = 4) were separately analyzed. RESULTS: Exhausted subjects displayed a reduced range of vagal cardiac control on the workday; and both high strain and exhausted subjects displayed reduced short-term variance in vagal cardiac control. A repeated measures ANOVA controlling for age confirms reductions in variance of cardiac vagal activity in high job strain subjects (0.01), with further reductions in subjects reporting exhaustion (p = 0.001). CONCLUSION: This analysis supports the hypothesis that (a) job strain is associated with reductions in cardiac vagal - or system level - variance; and (b) that reduced system variability may be a characteristic of exhaustion.

Psychosocial working conditions and active leisure-time physical activity in middle-aged us workers.

OBJECTIVES: This study was to examine whether psychosocial work characteristics such as job control, psychological job demands, and their combinations are associated with leisure-time physical activity (LTPA) in US workers. MATERIALS AND METHODS: 2019 workers (age range: 32 to 69) from the National Survey of Midlife Development in the United States (MIDUS) II study (2004-2006) were chosen for this cross-sectional study. Job control and job demands were measured by standard questionnaire items. Active LTPA was defined as "moderate or vigorous" level of physical activity. RESULTS: After controlling for covariates (e.g., age, race, education, income, physical effort at work, obesity, and alcohol consumption), high job control was associated with active LTPA. Active jobs (high control and low demands) and low-strain jobs (high control and high demands), compared to passive jobs (low control and low demands), increased the odds for active LTPA. The associations varied by sex and education level. Job demands alone were not associated with active LTPA. CONCLUSIONS: Having on-the-job learning opportunities and decision authority on their tasks may be conducive to active LTPA in middle-aged US workers.

Sedentary work, low physical job demand, and obesity in US workers.

BACKGROUND: Little is known about the role of low physical activity at work (sedentary work or low physical job demand) in the increasing prevalence of obesity of US workers. METHODS: This cross-sectional and secondary data analysis included 1,001 male and 1,018 female workers (age range: 32-69) from the National Survey of Midlife Development in the United States (MIDUS) II study (2004-2006). Sedentary work and physical job demand were measured by questionnaire items. Total obesity (based on body mass index) and central obesity (based on waist circumference) were defined using WHO criteria. RESULTS: After controlling for covariates (socio-demographic, psychosocial working conditions, health status, and health behaviors), sedentary work, low physical job demand, or their combination increased the risk for total and central obesity in male workers, particularly when they worked longer than 40 hr per week. Sedentary work marginally increased the risk for total and central obesity in female workers. CONCLUSIONS: Low physical activity at work is a significant risk factor for total and central obesity in middle-aged US male workers.

Conflict between the work and family domains and exhaustion among vocationally active men and women.

Exhaustion is consistently found to be more prevalent in women than in men. Women suffer from job strain more often, which may constitute a partial explanation for this phenomenon, but experienced shortcomings in combining work and family demands may also contribute to ill health. The aim of this study was to investigate, and analyse by gender, how work-related and family-related factors, as well as the interface between them, i.e. work-to-family conflict (WFC) and family-to-work conflict (FWC), are related to exhaustion. The study was cross-sectional with self-administered questionnaires assessing exposures and outcome with previously well-validated instruments. The participants were 2726 men and 2735 women, aged 45-64, vocationally active, and residing in Malmö, Sweden. Sixteen percent of the women and 8% of the men considered themselves exhausted. WFC, FWC, job strain, and low job support were all strongly correlated to exhaustion in both genders. In the multivariate analyses, adjusting for other work and family risk factors, WFC and FWC remained statistically significant risk factors for exhaustion in both men and women. Job strain, low job support, and having a somatic disorder were also independently associated with exhaustion. While WFC was more prevalent among men, it was more strongly associated with exhaustion in women than in men. In women, WFC and FWC contributed to a larger part of the explanatory power of the model, which amounted to 22% of the variance in women and 14% in men. The results imply that the concept of 'work stress' should be regarded in a wider context in order to understand gender related issues of exhaustion among vocationally active individuals.

Description of a large-scale study design to assess work-stress-disease associations for cardiovascular disease.

We claim that a new level of studies is needed to answer a series of important questions about the expanding global chronic disease burden for cardiovascular disease (CVD) and for related conditions such as diabetes, metabolic syndrome, and obesity. These require a new study design structure, related to a new level of theory that goes beyond the current single-factor, a-theoretic epidemiological studies. This new platform for the design of large-scale Work/Stress/Disease studies would assess CVD-related disease mechanisms in a more general and dynamic form, based on the use of new tools for measuring autonomic functions in an occupational stress context and a new theory of disease causation. A sample outline is presented for such a study, based on Stress-Disequilibrium Theory (SDT) hypotheses, building on analytic tools developed for the assessment of stress-related exhaustion effects and chronic disease risks from Heart Rate Variability (HRV) research studies. The goal is to assess the associations between social organizational risks, particularly at work, and hypertension, metabolic syndrome, and diabetes II. The study design is multi-stage, spanning across several levels of disease-related de-regulation, and addressing co-morbidity of the conditions themselves. The study design is meant to span across a broad social population at all levels and would probably be multi-site, involving several countries, to yield the larger sample increased power for finding associations for work - physiological effects.

Cross-language differential item functioning of the job content questionnaire among European countries: the JACE study.

BACKGROUND: Little is known about cross-language measurement equivalence of the job content questionnaire (JCQ) PURPOSE: The purposes of this study were to assess the extent of cross-language differential item functioning (DIF) of the 27 JCQ items in six languages (French, Dutch, Belgian-French, Belgian-Dutch (Flemish), Italian, and Swedish) from six European research centers and to test whether its effects on the scale-level mean comparisons among the centers were substantial or not. METHOD: A partial gamma coefficient method was used for statistical DIF analyses where the Flemish JCQ was the reference for other language versions. Additionally, equivalence between the Flemish and Dutch translations was subjected to a judgmental review. RESULTS: On average, 36% to 39% of the total tested items appeared to be cross-language DIF items in the statistical analyses. The judgmental review indicated that half of the DIF items may be associated with translation difference. The impacts of the DIF items on the mean comparisons of the JCQ scales between the centers were non-trivial: underestimated skill discretion (Milan), underestimated decision authority (Leiden), underestimated psychological demands (Milan women), and incomparable coworker support (Gothenburg 95). CONCLUSION: Cross-language DIF of the JCQ among European countries should be considered in international comparative studies on psychosocial job hazards using JCQ scales.

Sleeping problems as a risk factor for subsequent musculoskeletal pain and the role of job strain: results from a one-year follow-up of the Malmö Shoulder Neck Study Cohort.

BACKGROUND: The role of sleeping problems in the causal pathway between job strain and musculoskeletal pain is not clear. PURPOSE: To investigate the impact of sleeping problems and job strain on the one-year risk for neck, shoulder, and lumbar pain. METHOD: A prospective study, using self-administered questionnaires, of a healthy cohort of 4,140 vocationally active persons ages 45-64, residing in the city of Malmo. RESULTS: At follow-up, 11.8% of the men and 14.8% of the women had developed pain. The odds ratios (OR) for pain at follow-up and sleeping problems at baseline were 1.72 (95% CI: 1.13-2.61) in men and 1.91 (1.35-2.70) in women. Regarding exposure to job strain, ORs were 1.39 (0.94-2.05) for men and 1.63 (1.18-2.23) for women. These statistically significant risks remained so when controlled for possible confounding. A modest synergistic effect was noted in women with concurrent sleeping problems and job strain, but not in men. CONCLUSION: One in 15-20 of all new cases of chronic pain in the population could be attributed to sleeping problems. No evidence was found for a causal chain with job strain leading to musculoskeletal pain by the pathway of sleeping problems.

A cross-national study on the multidimensional characteristics of the five-item psychological demands scale of the Job Content Questionnaire.

BACKGROUND: The five-item psychological demands scale of the Job Content Questionnaire (JCQ) has been assumed to be one-dimensional in practice. PURPOSE: To examine whether the scale has sufficient internal consistency and external validity to be treated as a single scale, using the cross-national JCQ datasets from the United States, Korea, and Japan. METHOD: Exploratory factor analyses with 22 JCQ items, confirmatory factor analyses with the five psychological demands items, and correlations analyses with mental health indexes. RESULTS: Generally, exploratory factor analyses displayed the predicted demand/control/support structure with three and four factors extracted. However, at more detailed levels of exploratory and confirmatory factor analyses, the demands scale showed clear evidence of multi-factor structure. The correlations of items and subscales of the demands scale with mental health indexes were similar to those of the full scale in the Korean and Japanese datasets, but not in the U.S. data. In 4 out of 16 sub-samples of the U.S. data, several significant correlations of the components of the demands scale with job dissatisfaction and life dissatisfaction were obscured by the full scale. CONCLUSION: The multidimensionality of the psychological demands scale should be considered in psychometric analysis and interpretation, occupational epidemiologic studies, and future scale extension.

Testing two methods to create comparable scale scores between the Job Content Questionnaire (JCQ) and JCQ-like questionnaires in the European JACE Study.

BACKGROUND: Scale comparative properties of "JCQ-like" questionnaires with respect to the JCQ have been little known. PURPOSE: Assessing validity and reliability of two methods for generating comparable scale scores between the Job Content Questionnaire (JCQ) and JCQ-like questionnaires in sub-populations of the large Job Stress, Absenteeism and Coronary Heart Disease European Cooperative (JACE) study: the Swedish version of Demand-Control Questionnaire (DCQ) and a transformed Multinational Monitoring of Trends and Determinants in Cardiovascular Disease Project (MONICA) questionnaire. METHOD: A random population sample of all Malmo males and females aged 52-58 (n = 682) years was given a new test questionnaire with both instruments (the JCQ and the DCQ). Comparability-facilitating algorithms were created (Method I). For the transformed Milan MONICA questionnaire, a simple weighting system was used (Method II). RESULTS: The converted scale scores from the JCQ-like questionnaires were found to be reliable and highly correlated to those of the original JCQ. However, agreements for the high job strain group between the JCQ and the DCQ, and between the JCQ and the DCQ (Method I applied) were only moderate (Kappa). Use of a multiple level job strain scale generated higher levels of job strain agreement, as did a new job strain definition that excludes the intermediate levels of the job strain distribution. CONCLUSION: The two methods were valid and generally reliable.

High job strain and ambulatory blood pressure in middle-aged men and women from the Belgian job stress study.

OBJECTIVE: The aim of this study was to assess whether job strain is associated with 24-hour ambulatory blood pressure measurements within a subsample of the Belgian Job Stress Project (BELSTRESS) population. METHODS: A group of 89 middle-aged male and female workers perceiving high job strain and an equally large group of workers perceiving no high job strain wore an ambulatory blood pressure monitor for 24 hours on a regular working day. RESULTS: Mean ambulatory blood pressure at work, at home, and while asleep was significantly higher in workers with job strain as compared with others. The associations between job strain and ambulatory blood pressure were independent from the covariates. CONCLUSIONS: Within this study, high job strain was an important independent risk factor for higher ambulatory blood pressure at work, at home, and during sleep in a group of men and women.

Psychometric properties of the Korean version of the job content questionnaire: data from health care workers.

OBJECTIVES: To test the validity and reliability of selected scales, namely, decision latitude, psychological job demand, social support, job insecurity, and macro-level decision latitude from the Korean version of the job content questionnaire (K-JCQ), as part of a psychosocial epidemiological study among university hospital workers. METHODS: K-JCQ was developed by translation and back translation complying with the JCQ usage policy, and its psychometric properties were explored among 338 workers (290 females and 48 males) in a university hospital in Korea. Internal consistency was examined using Cronbach's alpha correlation coefficients. Factorial validity was tested using exploratory factor analysis. Pearson's correlation coefficients were used for test-retest reliability among a subset of 157 workers who responded to a repeat survey. Criterion-related validity was assessed by investigating the effects of the scales on job satisfaction and self-identity through work in multiple regression models. RESULTS: Cronbach's alpha for all selected scales was higher than 0.6, except for job insecurity (0.53) and macro-level decision authority (0.52), indicating appropriate internal consistency. Correlation coefficients between test and retest scales of decision latitude, psychological job demand, and social support were 0.60, 0.41, and 0.35, respectively. Exploratory factor analysis found three- and four-factor models, i.e., with and without macro-level decision latitude, respectively, closely corresponding to the theoretical constructs. High levels of decision latitude and social support, and low levels of psychological job demand and job insecurity were significantly associated with high level of job satisfaction. Higher self-identity through work was positively related to decision latitude and social support. CONCLUSIONS: These findings suggest that K-JCQ is valid and reliable for assessing psychosocial job stress among Korean workers. Macro-level decision latitude showed a separate factorial structure and was strongly associated with task-level decision latitude.