State IQ and suicide rates in the United States

Percept Mot Skills. 2007 Aug;105(1):102-6. doi: 10.2466/pms.105.1.102-106.


Previous findings pertaining to the direction (positive or negative) of the ecological correlation between intelligence and suicide rates in the USA have been conflicting. Using novel state IQ estimates, derived from the Scholastic Assessment Test, the American College Test, these tests combined, or the National Assessment of Educational Progress state scores, these estimates were not consistently associated to state suicide rates. Whereas ACT-derived state IQ was significantly positively correlated with suicide rates, the correlation with composite ACT-SAT-derived state IQ was significantly negative and with both SAT-derived and NAEP-derived state IQ also negative but not significant. Validity checks pointed to possible methodological problems with the state IQ estimates. Currently available estimates of state IQ, therefore, seem not appropriate to resolve the question of the direction of the ecological correlation of intelligence and suicide mortality across the USA.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Cause of Death / trends
  • Educational Measurement / statistics & numerical data*
  • Educational Status
  • Humans
  • Intelligence / classification*
  • Intelligence Tests / statistics & numerical data
  • Population Dynamics
  • Reproducibility of Results
  • Research Design / standards
  • Suicide / statistics & numerical data*
  • Suicide / trends
  • United States / epidemiology