Cross-sectional analysis of intimacy, passion, and commitment: testing the assumptions of the triangular theory of love.

Using data from two previous studies, the current study tested the assumptions in the Triangular Theory of Love about changes in intimacy, passion, and commitment over time. Using a cross-sectional design, the study examined differences in the three components among 446 romantically involved individuals who were either casually dating, exclusively dating, engaged, or married. In support for the assumptions in the Triangular Theory specifically, analyses indicated significant negative partial correlations between intimacy and relationship length as well as between passion and relationship length. The correlation between commitment and relationship length was significant and positive. One-way analysis of variance of relational stage gave similar results. Reported intimacy and passion scores were lowest for participants who were casually dating, higher for participants who were engaged, and lower for married participants. Reported commitment scores increased from casually dating participants to the married participants.