The relationship between testosterone and aggression: a meta-analysis

In non-human animals, the relationship between testosterone and aggression is well established. In humans, the relationship is more controversial. To clarify the relationship, Archer conducted three meta-analyses and found a weak, positive relationship between testosterone and aggression. Unfortunat ely, each of the analyses included only five to six studies. The aim of the present study was to re-examine the relationship between testosterone and aggression with a larger sample of studies. The present analyses are based on 45 independent studies (N=9760) with 54 independent effect sizes. Only s tudies that reported a p-value or effect size were included in the analyses and the sample may underestimate the proportion of non-significant finding s in the population. Correlations ranged from -0.28 to 0.71. The mean weigh ted correlation (r=0.14) corroborates Archer's finding of a weak positive r elationship. (C) 2001 Elsevier Science Ltd. All rights reserved.