This study was later published in the American Journal of Sociology. Although the study did not have any hypothesis, it tested the extent to which each of the theories that attempt to explain why people are attracted to individuals of the same sex hold up using empirical data drawn from the National Longitudinal Study of Adolescent Health which was a nationwide representative sample of adolescent participants. Data was collected in waves. and the response rate was quite high each time. The study collected data on adolescents who were twins (monozygotic and dizygotic), siblings other than twins. twins with siblings, unrelated siblings and unrelated individuals. A total of 20,745 individuals were included for analysis. The study followed a qualitative methodology, and data was collected using at – home survey and interview techniques. Quantitative data was also collected for key issues and statistically analyzed. Given that the topic of sexuality can be rather sensitive, the data was collected using Audio Computer Assisted Self-Administered Interview. This extensive work led to the understanding that the ‘intrauterine transfer of hormones’ theory of same-sex attraction has not been supported, just as the theory if ‘Genetic influence’ has not if the socialization effect is discounted (Bearman and Bruckner, 2001). The Evolutionary model has also been discounted. The model that garnered strong support from the data was the model discussing the role of socialization in same-sex attraction. The group that showed the effect most was male participants with a female twin but no same-sex older sibling. 18.7% of respondents in this group mentioned a same-sex attraction. which is far higher than the 8.6% in the full sample studied (Bearman and Bruckner, 2001). Thus it seems that the emphasis on equality that exists in a household that has opposite-sex twins seems to help in exploring the homosexual identity.