FOMO’s apprehension of missing out and constant connection desire dimensions differentially correlate with problematic smartphone and social media use, but not with depression or generalized anxiety

The fear of missing out (FOMO) involves an apprehension of missing out on rewarding experiences, and a desire to continually stay connected with people. However, this two-dimension conceptualization of FOMO has not been properly empirically examined. We examined this two-factor model using confirmatory factor analysis in 326 American college students, and 433 Italian participants recruited through social media. We discovered that in both samples, the two-factor model fit well; e.g., the US sample’s comparative fit index (CFI) = .990, Tucker-Lewis Index (TLI) = .985; Italian sample’s CFI = .941, TLI = .917. The two-factor model fit significantly better than a one-factor model in both samples (ps<.001) (though magnitude of differences was small, with CFI differences ranging from .001–.007). In both samples, problematic social media use severity was more correlated (ps<.001) with FOMO’s constant connection desire factor (US sample r = .749; Italian sample r = .845) than apprehension of missing out factor (US sample r = .622; Italian sample r = .500). In the American sample, problematic smartphone use severity also correlated more (p < .001) with constant connection desire (r = .668) than apprehension of missing out (r = .587). However, in the American sample depression severity correlated equally (ps>.05) with FOMO’s constant connection desire (r = .466) and apprehension of missing out (r = .503) factors; generalized anxiety disorder symptoms also equally correlated (ps>.05) with FOMO’s constant connection desire (r = .470) and apprehension of missing out (r = .508). We discuss implications of our findings for measurement of FOMO, and FOMO’s relationship with problematic Internet use and negative affectivity