Within- and between-person effects in the relationship between effort-reward imbalance and depressive symptoms

Theory suggests that a stressful working environment negatively affects workers' health. However, methodological limitations in observational studies often restrict conclusions about observed relationships. In this study, we examined cross-lagged effects of effort-reward imbalance (ERI; i.e., an indicator of work stress) and mental health (i.e., depressive symptoms) at the within-person level, while accounting for between-person variability. We used data from five panel waves gathered in the Survey of Health, Ageing and Retirement in Europe (SHARE), comprising N = 5,778 (self-)employed individuals aged 50 years or older. Repeated measures for both ERI and depressive symptoms were modeled using random intercept cross-lagged panel modeling. The results showed no cross-lagged effects of ERI and depressive symptoms at the within-person level, but the intra-individual variations in ERI were positively related to the intra-individual variations in depressive symptoms at the same point in time. At the between-person level, it showed that individuals with generally higher levels of ERI tend to demonstrate generally higher levels of depressive symptoms. The findings question the notion that ERI and depressive symptoms influence each other over the course of time, but rather indicate that third variable effects account for observed relationships between these constructs.