Informant assessment: The Informant Five-Factor Narcissism Inventory

Area of Science:

• Psychology
• Personality Science
• Clinical Psychology

Background:

• Existing Five-Factor Model (FFM) personality disorder measures primarily use self-reports.
• Narcissism is characterized by self-description distortions, making informant reports valuable.
• No informant-report versions of FFM-based narcissism measures were available.

Purpose of the Study:

• To provide initial validation for the Informant Five-Factor Narcissism Inventory (IFFNI).
• To assess self-informant agreement on narcissism and its relation to social dysfunction.
• To compare the IFFNI's ability to differentiate grandiose and vulnerable narcissism with existing measures.

Main Methods:

• Study 1: Compared informant reports (friends, partners, family) with self-reports on the IFFNI, FFM personality, and social dysfunction in college students.
• Study 2: Assessed informant reports on the IFFNI, FFM, and Pathological Narcissism Inventory (PNI) for individuals identified as grandiose or vulnerable narcissists via MTurk.

Main Results:

• Study 1: Higher self-informant agreement for IFFNI Grandiose (G) narcissism compared to other measures; no agreement for IFFNI Vulnerable (V) narcissism.
• Informant reports linked both IFFNI-G and V to social dysfunction, while self-reports only linked IFFNI-V.
• Study 2: IFFNI effectively distinguished G and V narcissism, with results comparable to the PNI informant profile.

Conclusions:

• The IFFNI demonstrates utility as an informant-based measure of narcissism.
• Informant perspectives offer unique insights into the social dysfunction associated with both grandiose and vulnerable narcissism.
• The IFFNI complements self-report measures by providing external validation and identifying discrepancies.