Shiratori et al. (2014)

Shiratori, Y., Tachikawa, H., Nemoto, K., Endo, G., Aiba, M.(相羽美幸), Matsui, Y.(松井豊), & Asada, T. (2014).
Network analysis for motives in suicide cases: A cross-sectional study.
Psychiatry and Clinical Neurosciences. Article first published online 
doi: 10.1111/pcn.12132
Suicide victims have various distresses or motives. There are few studies on how these motives toward suicide relate with each other. We used network analyses to extract the structures of correlations among the motives for suicide.
We obtained datasets of suicide victims from 2007–2009 in Japan in cooperation with Ibaraki Prefectural Police Headquarters. The data were analyzed by network centrality measures and a structural analysis by block modeling.
Among the motives, depression and physical illness showed relatively high scores of ‘degree centrality’, whereas depression and unemployment showed relatively high scores of ‘betweenness centrality’. Structural analysis by block modeling resulted in eight blocks. The most important block comprised eight motives, including conflict between parent and child, marital conflict, economic hardship, and overloaded with debt.
Depression and physical illness were important and priority areas for completed suicides, although these two motives had different influences on suicide behaviors. Furthermore, structural analysis revealed the important role of a block, including some familial and financial motives, which induced hopelessness. Our results suggest that it might be useful to consider the common ways in which motivations for suicide are tied together when suicide intervention is launched from a social model point of view.”