RESUMO
Abstract Background There is an interrelationship between the concepts of social exclusion, compulsive buying behavior, fear of missing out (FoMO), and narcissism. Nevertheless, the extent to which these concepts mediate or moderate their relationships with each other has not been efficiently investigated. Objective This research aims to investigate how FoMO mediates and narcissism moderates the correlation between social exclusion and compulsive buying behavior. In addition, the research aims to test a conceptual model and highlight the differences that may occur in the conceptual model proposed in two different countries. Methods This model was analyzed among 1007 university students (Turkey =506, Denmark =501). The study used scales to measure social exclusion, compulsive buying behavior, FoMO, and narcissism. The study employed PROCESS Model 4 to analyze direct and indirect (mediation) effects and PROCESS Model 59 to assess conditional (moderation) effects. Furthermore, the Johnson-Neyman technique was utilized to investigate interaction terms. Results The findings indicate that those who face social exclusion tend to participate more in compulsive buying, and this connection is partly explained by FoMO. This suggests that individuals who encounter social exclusion may have an increased likelihood of experiencing FoMO, which may subsequently contribute to compulsive buying behavior. Furthermore, the moderating effect of narcissism differed between the Turkey and Danish samples. Specifically, in the Turkey sample, narcissism only modified the connection between social exclusion and FoMO, while in the Danish sample, it impacted both the connection between social exclusion and FoMO and the connection between FoMO and compulsive buying. Conclusion The obtained results show that the regulating role of narcissism is different in Turkey and Denmark within the conceptual model we studied.