Considering models for depressive symptoms, we observed that each stressor was predictive of greater depressive symptoms, both in models that estimated the effect of each stressor independently (Model 1b) and in models that considered all eight stressors simultaneously (Model 2b). Each additional stressor was associated with an increase in depressive symptoms (Model 3b); Model 4b shows that every stressor (life events only marginally significant) was associated with depressive symptoms when adjusting for all other stressors and the number of stressors. In addition, the coefficients for the number of stressors showed a subadditive pattern, as indicated by the increasingly negative coefficients for number of high stress domains. That is, although depressive symptoms increased with the number of stressors (Model 3), once adjusted for the types of stressors, the increasing risk of depressive symptoms with the increasing number of stressors occurs at a significantly decreasing rate as the number of these stressors increase.
