Suicide rates, national intelligence estimates, and differential K theory

Area of Science:

• Evolutionary psychology
• Sociology
• Demography

Background:

• Differential K theory proposes a superordinate factor (K factor) influencing life history and reproductive strategies.
• Previous research indicated positive associations between suicide rates and cognitive ability at the population level.

Purpose of the Study:

• To investigate the relationship between national suicide rates and the K factor.
• To integrate findings on suicide and cognitive ability within the framework of differential K theory.

Main Methods:

• Cross-national analysis using data from 75 countries.
• Correlational study examining suicide rates against national intelligence estimates, longevity, affluence, birth rates, infant mortality, HIV/AIDS, and crime rates.

Main Results:

• Higher national suicide rates were positively associated with higher K factor levels.
• Countries with high suicide rates also exhibited higher intelligence estimates, longevity, and affluence.
• Conversely, high suicide rate countries showed lower rates of births, infant mortality, HIV/AIDS, and certain crimes.

Conclusions:

• The K factor is a positive correlate of suicidal behavior propensity at the population level.
• Findings support the integration of suicide rates and cognitive variables within differential K theory's conceptual space.
• Societal development indicators are linked to national suicide patterns.