PhD student: Chloé Vainqueur

Title : Adolescent digital use: characterization and sociodemographic and psychological factors associated with mental health in the EDEN and Elfe cohorts

Supervisors: Jonathan Bernard et Barbara Heude

Doctoral school : École doctorale Pierre Louis de Santé Publique (ED393)

Promotion : 2025-2028

Funding: Université Paris Cité (contrat doctoral)

Thesis abstract

Screens are part of everyday life: they can be found at home, at school, at work, and even in public spaces. It would appear that screen time among adolescents and young adults is on the rise, but there is a few public epidemiological data available to reliably verify the trend.
In addition, many concerns have been raised about the role of digital use in general, and social media in particular, on the mental health of adolescents, leading to mental health being designated as the Great National Cause for 2025. According to the 2021 Health Barometer, the prevalence of depressive episodes among young adults has been on the rise since 2010, with an acceleration since the Covid-19 pandemic.
Studies suggest a weak to moderate association between screen exposure and mental health in adolescents, however, this literature remains inconclusive due to methodological limitations.

The objective of my PhD is therefore to characterize adolescents’ digital uses and to study the sociodemographic and psychological factors associated with their mental health. During these three years, I will attempt to 1) characterize adolescents’ digital usage, 2) create trajectories of digital usage from childhood and analyze the associated sociodemographic and behavioral factors, and 3) examine psychological traits as potential moderators of the associations between digital usage and mental health.