Psychometric properties and differential explanation of a short measure of effort-reward imbalance at work: A study of industrial workers in Germany

Background: We test the psychometric properties of a short version of the Effort-Reward Imbalance (ERI) questionnaire in addition to testing an interaction term of this model's main components on health functioning. Methods: A self-administered survey was conducted in a sample of 2,738 industrial workers (77% men with mean age 41.6 years) from a large manufacturing company in Southern Germany. The internal consistency reliability, structural validity, and criterion validity were analyzed. Results: Satisfactory internal consistencies of the three scales: "Effort", "reward", and "overcommitment", were obtained (Cronbach's alpha coefficients 0.77, 0.82, and 0.83, respectively). Confirmatory factor analysis showed a good model fit of the data with the theoretical structure (AGFI = 0.94, RMSEA = 0.060). Evidence of criterion validity was demonstrated. Importantly, a significant synergistic interaction effect of ERI and overcommitment on poor mental health functioning was observed (odds ratio 6.74 (95% CI 5.32-8.52); synergy index 1.78 (95% CI 1.25-2.55)). Conclusions: This short version of the ERI questionnaire is a reliable and valid tool for epidemiological research on occupational health. Am. J. Ind. Med. 55:808-815, 2012. © 2012 Wiley Periodicals, Inc

Work stress is associated with diabetes and pre-diabetes: cross-sectional results from the MIPH Industrial Cohort Studies

Background: Diabetes is rapidly rising globally, and the relation of psychosocial stress in workplace to diabetes and prediabetes is not well investigated. Purpose: The aim of the study was to examine the association of work stress with diabetes and prediabetes in a sample of German industrial workers. Method: In this cross-sectional survey of an occupational cohort (n = 2,674, 77 % male), work stress was measured by the Effort-Reward Imbalance (ERI) Questionnaire. Diabetic status, i.e., diabetes and prediabetes, were diagnosed by glycated hemoglobin A1c criterion or fasting plasma glucose criterion supplemented by self-reports. Results: The overall prevalence rates of diabetes and prediabetes were 3.5 and 42.2 %, respectively. Using ordinal logistic regression with adjustment for potential confounding factors, high ERI at work was associated with diabetes-related ordinal variable (odds ratio [OR], 1.27; 95 % confidence interval [95 % CI], 1.02-1.58) and prediabetes-related ordinal variable (OR, 1.26; 95 % CI, 1.01-1.58) in men, whereas the associations in women were somewhat less pronounced and did not reach statistical significance. Conclusion: The findings indicate that work stress in terms of ERI is associated with diabetes and prediabetes in German industrial male workers. If supported by prospective evidence, results point to a new approach towards primary prevention of diabetes