Correlating homicide and suicide.

BACKGROUND The relationship between homicide and suicide has been studied extensively, but with conflicting results. The primary objective of this study was to examine the correlation between homicide and suicide rates in a large cross-sectional sample of UN member states. METHODS The study used age-standardized data on homicide and suicide for 65 international locales compiled by the World Health Organization. Weighted correlation coefficients between homicide and suicide rates were computed by sex, income level, and geographic region. RESULTS The overall correlation between homicide and suicide rates was weak and statistically insignificant (rho = -0.08, P = 0.5178). However, when analysed by geographic region the data revealed two distinct patterns: homicide and suicide rates were positively correlated in European countries (rho = 0.89, P < 0.0001), but negatively correlated in the Asia Pacific Region (rho = -0.97, P < 0.0001), and the Americas (rho = -0.62, P < 0.005). CONCLUSIONS The strength and direction of the relationship between homicide and suicide vary significantly with geographic region. The divergent geographic patterns in the relationship between homicide and suicide might be due to regional differences in social and cultural variables.