Job characteristics and employee well-being: a test of Warr's Vitamin Model in health care workers using structural equation modelling

Warr's (1987) Vitamin Model was investigated in a representative sample of 1437 Dutch health care workers (i.e. nurses and nurses' aides). According to this model, it was hypothesized that three job characteristics (i.e. job demands, job autonomy, and workplace social support) are curvilinearly related with three key indicators of employee well-being (i.e. job satisfaction, job-related anxiety, and emotional exhaustion). Structural equation modelling (LISREL 8) was employed to test the comprehensive Vitamin Model. The results showed that the fit of the non-linear model is superior to that of the linear model. Except for the relationship between job autonomy and emotional exhaustion, the curvilinear relationships followed the predicted U-shaped or inverted U-shaped curvilinear pattern. Moreover, it appeared that the three job characteristics are differentially related with various indicators of employee well-being. In conclusion, this study partially supports the assertion of the Vitamin Model that non-linear relationships exist between job characteristics and employee well-being. © 1998 John Wiley & Sons, Ltd.