Is using TikTok stressful? Exploring the longitudinal relationships between adolescents' self-concept clarity and digital stress.

TikTok is a pervasive and controversial social media platform with a sizeable adolescent following. Using a two-wave longitudinal design spaced 3 months apart during the academic year (N = 328, 60.4% male, M = 16.99), we investigated how adolescents' self-concept clarity relates to approval anxiety, fear of missing out, and online vigilance as possible stressors experienced on TikTok. Results showed a negative bidirectional link between self-concept clarity and approval anxiety. We also found a negative unidirectional longitudinal association between self-concept clarity and fear of missing out (FoMO) and online vigilance, respectively. Last, we found that approval anxiety longitudinally fosters fear of missing out. These findings suggest that adolescents holding uncertain self-views are more likely to perceive TikTok as a stressful environment and that experiencing approval anxiety might be especially harmful for them.