Relationship of IQ to Suicide and Homicide Rate: An International Perspective

Abstract

IQs were correlated with the z score of suicide rate minus z score of homicide rate using nine regions of the world--established market economies, formerly socialized Europe, India, China, other Asian nations, Sub-Saharan Africa, Latin America/Caribbean, Middle East Crescent, and the USA. Correlations were .85 and .83 with crude rates and age-adjusted rates, respectively. The homicide findings are consistent with previous research in individual countries showing that less intelligent persons commit homicide more often. However, the present findings of a positive correlation between IQ and suicide rates are the opposite of what has been found in the more definitive studies within countries. Explanations for the apparent paradox and for the findings more generally were offered.