The measurement of effort–reward imbalance at work: European comparisons

Using comparative data from five countries, this study investigates the psychometric properties of the effort–reward imbalance (ERI) at work model. In this model, chronic work-related stress is identified as non-reciprocity or imbalance between high efforts spent and low rewards received. Health-adverse effects of this imbalance were documented in several prospective and cross-sectional investigations. The internal consistency, discriminant validity and factorial structure of ‘effort’, ‘reward’, and ‘overcommitment’ scales are evaluated, using confirmatory factor analysis. Moreover, content (or external) validity is explored with respect to a measure of self-reported health. Data for the analysis is derived from epidemiologic studies conducted in five European countries: the Somstress Study (Belgium; n=3796), the GAZEL-Cohort Study (France; n=10,174), the WOLF-Norrland Study (Sweden; n=960), the Whitehall II Study (UK; n=3697) and the Public Transport Employees Study (Germany; n=316). Internal consistency of the scales was satisfactory in all samples, and the factorial structure of the scales was consistently confirmed (all goodness of fit measures were >0.92). Moreover, in 12 of 14 analyses, significantly elevated odds ratios of poor health were observed in employees scoring high on the ERI scales. In conclusion, a psychometrically well-justified measure of work-related stress (ERI) grounded in sociological theory is available for comparative socioepidemiologic investigations. In the light of the importance of work for adult health such investigations are crucial in advanced societies within and beyond Europe.