Stability and Change in Narcissism From Adolescence to Emerging Adulthood: Findings From a Longitudinal Study of Mexican-Origin Youth

The present study examined stability and change in narcissism during adolescence and emerging adulthood, a time of turbulent transitions and shifting social roles. Using data from a longitudinal study of 674 Mexican-origin youth, we investigated rank-order stability and mean-level change in narcissistic grandiosity from age 14 to 26 and narcissistic vulnerability from age 19 to 26. Grandiosity and vulnerability showed moderate-to-high stability across 2- to 3-year intervals ( rs = .43–.75) and across the full study period. On average, grandiosity increased from age 14 to 26 and vulnerability increased from age 19 to 26. However, these overall trends obscured significant individual-level changes, with about one third of the sample declining or showing no change in narcissism. Thus, although most individuals become more narcissistic from adolescence to emerging adulthood, many do not, and future research should identify factors that explain why some people increase and others decrease during the critical transition into adulthood.