Psychometric Properties and Measurement Invariance of the Borderline Personality Features Scale for Children...

We examined the psychometric properties of the Borderline Personality Features Scale for Children (BPFSC-11) in a sample of n = 235 adolescents. This involved an exploratory factor analysis (EFA) and a confirmatory factor analysis (CFA). We meticulously assessed internal consistency, convergent, and concurrent validity by analyzing the relationship between BPFSC-11 scores and measurements of emotional dysregulation, self-efficacy, resilience, depression, anxiety sensitivity, and social anxiety. The EFA revealed a two-factor solution, a finding that the CFA robustly confirmed. The BPFSC-11 demonstrated excellent internal consistency with an alpha value of 0.87 and adequate validity. Measurement invariance was examined across five groups: sex assigned at birth, born in Norway, speaking primarily Norwegian at home, by treatment group, and longitudinally. These findings confirm the reliability and validity of the BPFSC-11, adding new and significant findings to provide a solid foundation for its use in the assessment and treatment of adolescents with borderline personality features. Limitations of the current study include the absence of a clinical interview to examine diagnostic validity, and participants' responses may have been influenced by response desirability bias. Future research should examine the validity of the scale, both cross-sectionally and longitudinally, to enhance understanding of its application in different cultural contexts.