Exploring network structure and central items of the Narcissistic Personality Inventory
Narcissism has been defined as the ability to maintain a positive self‐image despite various internal and external processes. Narcissistic subjects have a need for self‐enhancing experiences from their social environment (Pincus et al., 2009). Narcissism has been theorized to possess both normal and pathological aspects, which have been considered by some authors as two different personality constructs (Von Kanel, Herr, Van Vianen, & Schmidt, 2017) and as a continuum by others (Paulhus, 1998). Grandiosity and vulnerability are considered as the two expressions of narcissism (Cain, Pincus, & Ansell, 2008): grandiose narcissism is associated with the predisposition to exploit others, a lack of empathy and one’s feelings of entitlement and superiority, whether vulnerable narcissism is associated with a depleted self‐image, social withdrawal and suicidality (Miller, Gentile, Wilson, & Campbell, 2013). The current gold‐standard models of narcissism, the trifucated model (Miller et al., 2016) and the narcissism spectrum model (Krizan & Herlache, 2018) postulate that grandiosity and vulnerability are two largely independent factors that are tied together by a core of entitlement.
The main tool used to study the construct of narcissism is the Narcissistic Personality Inventory (NPI; Raskin & Hall, 1979), which represents grandiose narcissism (Krizan & Herlache, 2018). The NPI consists of forty dichotomous items composed of both a narcissistic and a non‐narcissistic statement. The authors of the questionnaire propose seven domains of narcissism: authority reflects one’s need for authority and success (e.g., item 33 “I would prefer to be a leader”); exhibitionism represents one’s need to be the center of attention in a social context (e.g., item 30 “I like to be the center of attention”); superiority measures one’s belief of being better than other people (e.g., item 40 “I am an extraordinary person”); entitlement reflects one’s desire to receive respect and wield power (e.g., items 14 “I insist upon getting the respect that is due me” and 27 “I have a strong will to power”); exploitativeness represents one’s capacity to manipulate other people (e.g., item 13 “I find it easy to manipulate people”); self‐sufficiency measures one’s autonomy and belief in oneself (e.g., items 22 “I rarely depend on anyone else to get things done” and 34 “I am going to be a great person”); vanity measures one’s admiration of one’s own physical appearance (e.g., item 19 “I like to look at my body”). However, this seven‐domain structure of the NPI is controversial; several studies report different structures of the questionnaire, such as a four‐factor model (Emmons, 1987) and a three‐factor model (Boldero, Bell, & Davies, 2015).
Despite inconsistent results in the exploration of dimensionality (Ackerman et al., 2011; Corry, Merritt, Mrug, & Pamp, 2008; Kubarych et al., 2004), narcissism is commonly understood as composed of domains that are interchangeable measures of the construct proposed. In the last decade, a new way of analyzing psychological constructs as complex systems has been proposed: the network approach (Borsboom, 2017). Such complex systems are uncovered in empirical studies with network models, that represent a given construct as emerging from mutual interactions of its components (Borsboom & Cramer, 2013).
The network approach has been used to analyze a number of mental disorders, such as depression (Mullarkey, Marchetti, & Beevers, 2018), posttraumatic stress disorder (Fried et al., 2018; Phillips et al., 2018). Psychological constructs such as personality (Costantini et al., 2015), empathy (Briganti, Kempenaers, Braun, Fried, & Linkowski, 2018) and self‐worth (Briganti, Fried, & Linkowski, 2019) have also been proposed as network structures. The Pathological Narcissism Inventory has been recently investigated through the lens of network analysis (Di Pierro, Costantini, Benzi, Madeddu, & Preti, 2019), which identified Contingent self‐esteem, Grandiose Fantasies and Entitlement Rage to be important traits of the constructs.