Analysis of impact of geographic characteristics on suicide rate and visualization of result with Geographic Information System.

Aim The aim of our study was to understand the geographic characteristics of Japanese communities and the impact of these characteristics on suicide rates. Methods We calculated the standardized mortality ratio from suicide statistics of 3318 municipalities from 1972 to 2002. Correlation analysis, multi-regression analysis and generalized additive model were used to find the relation between topographic and climatic variables and suicide rate. We visualized the relation between geographic characteristics and suicide rate on the map of Wakayama Prefecture, using the Geographic Information System. Results Our study showed that the geographic characteristics of each community are related with its suicide rate. The strongest factor among the geographic characteristics to increase the suicide rate was the slope of the habitable land. Conclusions It is necessary to take the characteristics of each community into consideration when we work out measures of suicide prevention. Visualization of the findings on the local map should be helpful to promote understanding of problems and to share the information among various parties in charge of suicide prevention.