Exposure to Fetal Testosterone, Physical Aggression, and Violent Behavior: A Meta-analysis of the 2D:4D Digit Ratio

• In Event: Recent Developments in Biosocial and Developmental Research

Abstract

Biological perspectives have become increasingly prominent among contemporary explanations of criminal and analogous behavior. Within this line of work, the role of biomarkers for criminogenic risk—including factors such as low resting heart rate and skin conductivity—are receiving more and more empirical attention. One such biomarker is the 2D:4D digit ratio—a purported indicator of exposure to fetal testosterone. A growing roster of studies has emerged that examines the link between the 2D:4D digit ratio and aggressive and violent behavior, yet this body of work has produced inconsistent results. Accordingly, in the present study we subject this literature to a meta-analysis to determine: (1) the overall mean effect size of the 2D:4D digit ratio to measures of physically aggressive and violent behavior, and (2) how stable/robust these effect sizes are to methodological variations across studies (e.g., different outcome measures, different kinds of samples). The broader purpose is to shed light on the extent to which the 2D:4D effects are large and stable enough to warrant continued scholarly attention.

Authors

• Travis C. Pratt, University of Cincinnati

• Jillian J. Turanovic, Florida State University

• Alex R. Piquero, University of Texas at Dallas