Can All Oxygen Molecules Accumulate in One Corner of the Room? Treating Pathological Narcissism Requires High Standard Randomized Clinical Trials. A Commentary on the Trial by Mohajerin et al.

Narcissistic personality disorder (NPD) and pathological narcissism (PN) urgently need empirically supported treatment options. Mohajerin et al. randomized controlled trial yielded promise in addressing this gap. However, in this commentary, an international group of personality disorder experts identify a number of issues with the trial methodology, reporting and interpretation: (i) the unlikeliness that consecutive sample recruitment would result in almost equal number of participants in grandiose vs. vulnerable subgroups; (ii) the unlikeliness that consecutive sample recruitment would result in almost equal number of participating men and women; (iii) the unlikely possibility that grandiose and vulnerable narcissism would appear as uncorrelated subtypes; (iv) dissimilar treatment responses to schema-focused therapy vs. Unified Protocol; (v) absence of dropouts; (vi) unclear randomization procedure; (vii) poor screening and recruitment procedures and limited transparency in trial registration; (viii) exclusive reliance on self-report measures; (ix) limited transparency in supervision and treatment fidelity procedures; (x) nonequivalence of treatment dose and duration; and (xi) lack of clarity on how the disclosure of NPD diagnosis to participants was handled in the trial. In light of these concerns, it is difficult to reconcile the results of this trial with the inherent challenges of treating NPD and PN. We therefore warrant against considering it a benchmark in NPD treatment innovation.