2D:4D and Self-Employment: A Preregistered Replication Study in a Large General Population Sample

Area of Science:

• Behavioral Economics
• Human Biology
• Psychology

Background:

• The 2D:4D digit ratio, comparing second to fourth finger length, is a proposed marker for prenatal testosterone exposure.
• Previous research suggested a link between the left-hand 2D:4D ratio and self-employment.

Purpose of the Study:

• To replicate the association between the 2D:4D digit ratio and self-employment.
• To investigate the relationship in a large, representative German adult sample.

Main Methods:

• A preregistered replication study was conducted.
• Data from over 2100 adults in the German Socioeconomic Panel-Innovation Sample (SOEP-IS) were analyzed.
• The left-hand 2D:4D digit ratio was calculated and compared with self-employment status.

Main Results:

• No statistically significant association was found between the 2D:4D digit ratio and self-employment in the SOEP-IS sample.
• The findings contrast with a prior study suggesting such a link.

Conclusions:

• The 2D:4D digit ratio does not appear to be a reliable predictor of self-employment in the studied German population.
• Further research is needed to explore potential biological or environmental factors influencing entrepreneurship.