Maartje Boer

CHAPTER 4 ADOLESCENTS’ INTENSE AND PROBLEMATIC SOCIAL MEDIA USE AND THEIR WELLBEING IN 29 COUNTRIES Maartje Boer, Regina J. J. M. van den Eijnden, Meyran Boniel-Nissim, Suzy- Lai Wong, Jo Inchley, Petr Badura, Wendy M. Craig, Inese Gobina, Dorota Kleszczewska, Helena J. Klanšček, and Gonneke W. J. M. Stevens Author Contributions MB, GS, and RvdE conceived of the study. MB conducted the literature review, data analyses, and drafted the initial and revised manuscript. GS and RvdE advised during all stages of preparing and revising the manuscript. JI was the international coordinator of the HBSC study. All authors critically reviewed the initial and reviewed manuscript, and approved of the final manuscript. Publication Boer, M., Van den Eijnden, R. J. J. M., Boniel-Nissim, M., Wong, S. L., Inchley, J. C., Badura, P., Craig, W. M., Gobina, I., Kleszczewska, D., Klanšček, H. J., & Stevens, G. W. J. M. (2020). Adolescents’ intense and problematic social media use and their well-being in 29 countries. Journal of Adolescent Health , 66 (6), S89-S99. https://doi.org/10.1016/j.jadohealth.2020.02.014