Re: 'changes in perceived job strain and the risk of major depression: results from a population-based longitudinal study'.

摘要

We read with interest a recent article in the American Journal of Epidemiology by Wang et al. (1), examining changes in job strain and the risk of major depression. Research describing how change in psychosocial working conditions impacts mental health status is needed to increase the awareness among policy makers and employers of the possible health ramifications of changing workplace organization and practices. However, the measurement of change between time points among individuals is a complex task (2-4), one which we feel that Wang et al. (1) may not have addressed with sufficient care. Similar to some others (5-7), Wang et al. (1) used the crossing of a threshold to indicate when respondents had "changed" in job strain. In their defense, they used a relatively meaningful cutpoint, that is, where job demands exceeded job control, an improvement on the use of an arbitrary cutpoint based on the median score. However, does a simple cutpoint allow us to know who has changed and who has not?