The Erikson Psychosocial Stage Inventory in Adolescent Samples

This study tested the factorial structure and equivalence of identity as measured by the Erikson Psychosocial Stage Inventory (EPSI; Rosenthal, Gurney, & Moore, 1981 ) in 2,666 adolescents ( M age = 16.53, SD = 1.50, 55% girls) in the United States and Japan. The EPSI Identity Scale is a widely used measure of the Eriksonian conceptualization of personal identity (i.e., individual self-knowledge, synthesis, and consistency) and is measured with two factors: identity confusion and synthesis. A bi-factor model for the EPSI had a better fit than a single- and two-factor model. Moreover, the EPSI results showed configural and partial metric equivalence, but did not show scalar equivalence across samples. Future cross-national research with adolescents from the United States and Japan may investigate correlates between identity, as measured by the EPSI, with other measures of interest. However, group comparisons among these samples may be ill advised due to a lack of scalar equivalence.