Globally, TikTok is now the fastest growing social media platform among children and young people; but it remains surprisingly under-researched in psychology and psychiatry. This is despite the fact that social media platforms have been subject to intense academic and societal scrutiny regarding their potentially adverse effects on youth mental health and wellbeing, notwithstanding the inconsistent findings across the literature. In this two part study, we conducted a systematic review concerning studies that have examined TikTok for any public health or mental health purpose; and a follow-up content analysis of TikTok within an Irish context. For study 1, a predetermined search strategy covering representative public and mental health terminology was applied to six databases - PSYCINFO, Google Scholar, PUBMED, Wiley, Journal of Medical Internet Research, ACM - within the period 2016 to 2021. Included studies were limited to English-speaking publications of any design where TikTok was the primary focus of the study. The quality appraisal tool by Dunne et al., (2018) was applied to all included studies. For study 2, we replicated our search strategy from study 1, and converted this terminology to TikTok hashtags to search within TikTok in combination with Irish-specific hashtags. As quantified by the app, the top two "most liked" videos were selected for inclusion across the following three targeted groups: official public health accounts; registered Irish charities; and personal TikTok creators. A full descriptive analysis was applied in both studies. Study 1 found 24 studies that covered a range of public and mental health issues: COVID-19 (n = 10), dermatology (n = 7), eating disorders (n = 1), cancer (n = 1), tics (n = 1), radiology (n = 1), sexual health (n = 1), DNA (n = 1), and public health promotion (n = 1). Studies were predominately from the USA, applied a content analysis design, and were of acceptable quality overall. In study 2, 29 Irish TikTok accounts were analysed, including the accounts of public health authorities (n = 2), charity or non-profit (n = 5), and personal TikTok creators (n = 22). The overall engagement data from these accounts represented a significant outreach to younger populations: total likes n = 2,588,181; total comments n = 13,775; and total shares n = 21,254. TikTok has been utilised for a range of public health purposes, but remains poorly engaged by institutional accounts. The various mechanisms for connecting with younger audiences presents a unique opportunity for youth mental health practitioners to consider, yet there were distinct differences in how TikTok accounts used platform features to interact. Overall, there is an absence of high quality mixed methodological evaluations of TikTok content for public and mental health, despite it being the most used platform for children and young people.
Keywords: Review; children; psychology; qualitative; tiktok.