The Self-Concept and Identity Measure in Adolescents Factor Structure, Measurement Invariance, and Associations with Identity, Personality Traits, and Borderline Personality Features

Identity difficulties have been associated with various psychiatric conditions and are considered a central issue in personality pathology. Following the Alternative Model for Personality Disorders, measures of self- and interpersonal functioning have been developed. Although these measures were intended to be separate ratings of self-other deficits, only a global rating was obtained. Moreover, these measures fall short in bridging the gap between developmental and clinical identity work. To capture both adaptive and disturbed identity dimensions, Kaufman et al. (2015) developed the Self-Concept and Identity Measure (SCIM) that assesses consolidated identity, disturbed identity, and lack of identity. Using two-wave longitudinal data (2,150 adolescents; 54.2% girls; age range = 12-19), this study investigated the factor structure and reliability of the Dutch SCIM, its measurement invariance across time, its longitudinal measurement invariance across gender and age groups, and associations of the SCIM with identity synthesis and confusion, Big-Five personality traits, and borderline personality disorder features. Consolidated identity scores were positively related to identity synthesis and adaptive Big-Five traits, whereas negatively related to identity confusion, neuroticism, and borderline features. Opposite associations were obtained for disturbed identity and lack of identity scores. The Dutch SCIM appeared to produce valid and reliable scores and seemed suited to assess longitudinal identity functioning in Belgian adolescents.