What finger length reveals about economic decisions: The relationship between digit ratio and cooperation, altruism and risk aversion: a systematic review and meta-analysis

Digit ratio, the ratio of the lengths of the index and ring fingers, serves as a biological marker for prenatal testosterone levels. As digit ratio is linked to status and rank in the workplace and society, it stands to reason that it may also explain differences in economic decisions and behaviour. Research often reveals a link between digit ratio and economic behaviours such as altruism, cooperation, delayed gratification and risk aversion. This study conducted the first meta-analysis of the existing literature. Twenty studies linked digit ratio to one or more of the economic behaviours mentioned above. The empirical section presents the results of the overall effect, the individual effects, publication bias, subgroup analyses and meta-regression analyses of these twenty studies. Finally, the results are interpreted and critically discussed, and an outlook on future research in this area is provided.