Peer-reviewed article
Tracking mental health and cognitive changes following the Australian social media minimum age legislation: a 4-wave longitudinal study protocol.
Bilston A, Brown L, Qi X, Morgan E, Hasan Y et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study will track Australian children aged 10-15 years over 18 months to understand how a new law prohibiting social media use under age 16 affects their mental health, well-being and thinking skills. Researchers will collect data from young people and their parents before and after the law takes effect in December 2025, using surveys, daily experience sampling, cognitive tests and recordings of actual app use. The study aims to identify what aspects of social media affect young people negatively and how parents and government policies might help protect them.
Key points
- 422 young people aged 10-15 years and their parents will be assessed at baseline (October-December 2025) and three follow-up timepoints over 18 months
- Data collection includes parent and adolescent surveys, ecological momentary assessments, cognitive tasks and smartphone-recorded app usage screenshots
- The study will use linear regression and mixed-effects models to examine relationships between social media use and mental health outcomes
- Findings will identify intervention opportunities at individual, parental and governmental levels to reduce negative impacts of social media
- Results will be shared through academic publications, conferences, infographics and videos for young people and parents
Limitations
This is a study protocol, not results. The study has not yet been conducted, so no evidence on outcomes is available. The design capitalises on natural policy variation but cannot definitively establish causation, only associations, and will be limited by participants' adherence to the law and potential unobserved confounding factors.
Abstract
Introduction Over the last two decades, increases in adolescent mental health difficulties have been recorded alongside a rapid expansion in social media use. In response to these trends, on 10 December 2025, the Australian government implemented Social Media Minimum Age legislation prohibiting Australians under the age of 16 years from having social media accounts. The introduction of this legislation allows for a unique quasi-experimental investigation of the impact of social media use on adolescent mental health and the mechanisms through which social media may impact young Australian adolescents' mental health, well-being and cognition. Methods and analysis To assess the relationship between social media use and young adolescents' mental health, well-being and cognition, a longitudinal mixed-methods approach will be taken. 422 young people (aged 10-15 years) and parent/carer dyads were recruited and invited to complete a baseline assessment before the implementation of the Social Media Minimum Age legislation (October-December 2025). Three follow-up assessments will then be completed after 6 (April-May 2026), 12 (October-November 2026) and 18 months (April-May 2027). Data from parent/carer and adolescent surveys, ecological momentary assessments (EMAs), cognitive tasks and smartphone-recorded screenshots of social media and messaging app use across each of these timepoints will be analysed. Linear regression analyses will be used to assess correlational relationships between social media experiences and responses and mental health outcomes as well as how individual factors moderate these relationships. To assess these relationships over time and between momentary experiences and responses (EMA data) and more stable trait-based (individual) and environmental (parenting and government restrictions) factors, we will use linear mixed-effects models and mixed-effects segmented regression. Ethics and dissemination This study has been approved by the UNSW Human Research Ethics Committee (iRECS 9197). Findings from this study will help identify potential opportunities for interventions at individual, micro (parental) and macro (governmental) levels to mitigate any negative impacts of social media for younger adolescents. Results will be disseminated through peer-reviewed publications, conference presentations, public engagement opportunities and researcher-associated websites. After each assessment timepoint, core findings will also be distilled into engaging formats such as infographics and videos, which will be shared with young people and their parent/carer.