The Job Demand-Control(-Support) model and psychological well-being: a review of 20 years of empirical research

The Job Demand-Control (JDC) model (Karasek, 1979) and the Job Demand-Control-Support (JDCS) model (Johnson, and Hall, 1988) have dominated research on occupational stress in the last 20 years. This detailed narrative review focuses on the JDC(S) model in relation to psychological well-being. It covers research from 63 samples, published in the period 1979-1997. In the review a distinction is drawn between two different hypotheses prevailing in research on the models. According to the strain hypothesis of the JDC model, employees working in a high-strain job (high demands-low control) experience the lowest well-being. The buffer hypothesis states that control can moderate the negative effects of high demands on well-being. Translating these hypotheses to the expanded JDCS model, the iso-strain hypothesis predicts the most negative outcomes among workers in an iso-strain job (high demands-low control-low social support/isolation), whereas the buffer hypothesis states that social support can moderate the negative impact of high strain on wellbeing. Although the literature gives considerable support for the strain and iso-strain hypotheses, support for the moderating influence of job control and social support is less consistent. The conceptualization of demands and control is a key factor in discriminating supportive from nonsupportive studies. Only aspects of job control that correspond to the specific demands of a given job moderate the impact of high demands on well-being. Furthermore, certain subpopulations appear to be more vulnerable to high (iso)strain, whereas others benefit more from high control. On the basis of the results of this review, suggestions for future research and theoretical development are formulated.