Advancing mediation analysis in occupational health research

The Mediating Effect of Unhealthy Behaviors and Body Mass Index in the Relation Between High Physical Workload and Self-Rated Poor Health in Male Construction Workers

“…However, advanced mediation methodology is emerging where limitations of more traditional mediation analysis can be better explored and used in future studies. 41 Next to the causality issue, the assumption of no unmeasured confounding or interaction of the exposure -mediator, mediator -outcome, and exposure -outcome relations could not be established in our study. The lack of adjustment for potential (unmeasured) confounding factors may have resulted in an overestimation of the findings.…”

“…In our study, the exposure and mediating factor were however measured at the same measurement, because we believed immediate effects would occur in health behaviors as a result of physical work demands rather than after 2 years. Despite we are aware of the required temporal sequence of the exposure, mediator, and outcome to ensure causality for a mediation analysis, 41 we think it is unlikely that the health behaviors had an effect on the work a construction worker does, which is generally carried out over a long period of time. Still, more research with three measurements, where the exposure is measured before the mediator, though preferably not with a long time frame in between, and the mediator measured before the outcome is recommended to verify our results.…”

Working conditions and health behavior as causes of educational inequalities in self-rated health: an inverse odds weighting approach

“…This method assesses mediation by estimating the reduction in the excess (health) risk of lower educational groups compared to the highest educational group after conditioning on the mediator(s). This approach, however, is only valid in linear models under the assumption that there is no interaction between the exposure and mediator on the outcome (18,19). Several studies have shown that this crucial assumption is often violated (18), also in studies on socioeconomic inequalities in health (15,20,21).…”

The mediating role of sleep, physical activity, and diet in the association between shift work and respiratory infections

“…In addition, an important assumption of the statistical model used in this study is that there is no unmeasured confounding or interaction of the exposure-mediator, mediator-outcome, and exposure-outcome relations. Currently, new mediation methodology is developing in which these assumptions can be further explored, which can be used in future work (41). As this is the first study using mediation analysis to study the role of lifestyle behaviors in the association between shift work and respiratory infections, more research is needed to replicate our findings.…”

“…To conduct mediation analysis, a longitudinal design is preferred, in which the exposure is measured before the mediator, and the mediator is measured before the outcome (41). Although in the current study, exposure and mediators were both measured at baseline, shift work exposure referred to performing shift work for ≥6 months prior to baseline.…”