Reis, H. T., Lin, Y., Bennett, E. S., & Nezlek, J. B. (1993). Change and consistency in social participation during early adulthood. Developmental Psychology, 29, 633-645.

This article reprots a longitudinal study of the social interaction patterns of college students and adults. Adults (N = 113) from 26 to 31 years old who had participated in similar studies in collge kept detailed records of social activity for 2 weeks. Three hypotheses were supported. First, from college to adulthood. opposite-sex socialzing grew, whereas same-sex, mixed-sex, and group interactions decreased. Second, intimacy increased in adulthood, whereas satisfaction did not. Contrary to theories that focus on the formation of primary intimate relationships in early adulthood, intimacy increased in all interaction categories. Sex differences in the develpment of intimacy were also noted. Third, correlations revealed marked consistency over time in several variables. Implications of these findings for social development during early adulthood were examined.