Fig. 2.

The strength (centrality) value (standardized Z scores) of the major depressive symptoms among junior high school students, senior high school students, college students, and elderly adults. The red dashed line indicates the core symptoms newly identified in this study (Top three). The blue dashed line denotes core symptoms that have been found in previous studies (Top three). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)