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A study published in Journal of Human Development and Capabilities looks at the age of smartphone ownership and mental health outcomes.
Prof Pete Etchells, Professor of Psychology and Science Communication, Bath Spa University, said:
“It’s difficult to fully assess this study, as there are very limited methodological and analytical details provided. While we are given a generalised overview of the Global Mind Project, there is no standardised methods section detailing how variables of interest were measured or operationalised, no demographic information, and no detailed outline of the analytic methods used. This makes it hard to assess the quality of the research conducted.
“The study averages a wide range of factors relating to mental health into a single composite score, and correlates this what appears to be a self-report measure of age of first smartphone ownership. The findings suggest some sort of negative relationship – i.e. that the younger the initial age of smartphone ownership, the worse the composite mental health score is. However, it’s not clear from the reported data the strength of these relationships, nor why ownership at age 5-6 is compared with an averaged ownership between age 13-18.
“The study then moves on to talk about age of access to social media accounts and potential associations to factors such as poor family relationships and cyberbullying, although again it’s not clear how these were measured. A series of regression analyses are then put in the context of access to AI-power social media environments, but I don’t quite see what this means or how it was measured. Later, AI-powered digital environments are mentioned, which is again a different concept that isn’t clearly defined.
“Given the correlational nature of the study, along with unclear definitions of key variables of interest and lack of methodological details, I was therefore surprised to see the paper end with a series of digital policy recommendations for under-13s. While some of these (e.g. digital literacy training) are sensible, it is not clear how they are informed by the study itself. This appears to be another study in a long line of papers that are based on correlational self-report data, and I’m not convinced that more studies along these lines are adding anything new to our understanding of digital technology effects. There is a wealth of complex and interacting factors that will impact on the initial age of smartphone ownership, access to social media and mental health, but it’s not clear how these are accounted for in this study. I would therefore be reluctant to suggest that there are any useful policy implications for this work.”
Prof Chris Ferguson, Professor of Psychology, Stetson University, said:
“I honestly wasn’t at all impressed with this study. First, the survey is both online and self-report, both qualities likely to bias the results. I took the survey myself (so now I’m a participant, I guess) and found it to be crude. The survey does not appear to be a well-validated clinical measure of mental health and there are no checks for unreliable responding. Self-report measures of mental health are now well-known to be unreliable and these questions only touch on mental health in crude non-diagnostic ways. Online samples are often unreliable, and don’t generalize to individuals who spend less time online. The analyses are merely descriptive without proper controls. The language of the study is inappropriately strong for such a crude correlational design lacking proper controls.”
‘Protecting the Developing Mind in a Digital Age: A Global Policy Imperative’ by Tara Thiagarajan et al. was published in Journal of Human Development and Capabilities at 5:01 UK time on Monday 21st July.
DOI: https://doi.org/10.1080/19452829.2025.2518313
Declared interests
Prof Pete Etchells: Pete Etchells is the author of Unlocked: The Real Science of Screen Time (and how to spend it better).
Prof Chris Ferguson: No conflicts of interest to declare.