In the fourth stage, mediation analyses were then computed, and the selected mediators (depressive symptoms and malnutrition) were entered to test the components of the mediation model (Model 4). The bootstrapping method was used to assess the indirect effects of the mediation model [62,63]. Thus, the mediation model was examined by directly testing the significance of the indirect effect of the independent variable (IV; feelings of loneliness) on the dependent variable (DV; subjective age) through the mediators (MeV; depressive symptoms and malnutrition), while controlling for background variables that had been identified in the bivariate analyses as significant.