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.
Mannheim Institute of Public Health, Social and Preventive Medicine, Heidelberg University, Mannheim, Germany. lijian1974@hotmail.com
Jian
J
Li
Adrian
A
Loerbroks
Marc N
MN
Jarczok
Ina
I
Schöllgen
Jos A
JA
Bosch
Daniel
D
Mauss
Johannes
J
Siegrist
Joachim E
JE
Fischer
D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005858:Germany; D006306:Health Surveys; D006801:Humans; D007221:Industry; D007588:Job Satisfaction; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016272:Occupational Health; D011581:Psychological Tests; D011594:Psychometrics; D015203:Reproducibility of Results; D012201:Reward; D013315:Stress, Psychological / Q000175:diagnosis*; D011795:Surveys and Questionnaires