The relationship between digit ratio and personality: 4D:5D digit ratio, sex, and the trait of conscientiousness

Sex differences cause differences in hormone levels, impacting many aspects of humans, including the digit ratio and personality. Due to this impact, we decided to investigate the effect of the 4D:5D digit ratio in influencing the personality trait of conscientiousness in female participants. Because research has suggested that a larger 4D:5D digit ratio could indicate more feminine characteristics, we hypothesized that greater conscientiousness would be expressed in females as compared to males. We performed this study by using two methods of data collection, which included quantitative digit ratio measurements and an online survey assessing personality traits. By looking at the relationship between sex and level of conscientiousness through the responses from our survey and the relationship between sex and 4D:5D digit ratio through measurements, we discovered that these findings support our hypothesis that there is a relationship between female sex and increased level of conscientiousness. However, we did not discover a direct relationship between right 4D:5D digit ratio and conscientiousness. Noting that this is an association rather than a causal factor, this suggests that sex-hormone driven differences are influencing the physical attributes of the digit ratio and the personality traits, including conscientiousness.