Psychometric Properties of the German Narcissism Inventory 90 (NI-90) in a clinical and non-clinical sample of adolescents: a comparative study.

Background: The Narcissism Inventory (NI) is a frequently used German inventory for measuring narcissism in clinical settings; an additional short version (NI-90) also exists. Psychometric properties of the NI-90 scales were examined in clinical and non-clinical adolescent samples.

Methods: Two adolescent samples were assessed with the NI-90: a non-clinical sample (n = 439, mean age ± SD = 15.