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expert reaction to problematic smart phone use in young people

A study, published in BMC Psychiatry, reports that an estimated 1 in 4 children and young people have ‘problematic’ smartphone usage.


Dr Sam Chamberlain, Wellcome Trust Clinical Fellow, Honorary Consultant Psychiatrist, University of Cambridge, said:

“Research into Problematic Smartphone Use is important from a public health point of view. The authors report that approximately 10-30% of young people in the studies included in their meta-analysis met a chosen threshold for having Problematic Smartphone Use. Also, Problematic Smartphone Use was associated with (by self-report measures) higher levels of depression, anxiety, and worse sleep. These results resonate with previous findings, including those on related topics such as Problematic Usage of the Internet.

“By using meta-analysis, the authors do a valuable service by synergising data, highlighting limitations in the existing literature, and identifying key future research directions.

“One challenge for the field, in light of this valuable meta-analysis, is that Problematic Smartphone Use is not consistently defined. There are various rating scales, with different cut-offs and criteria, some of which have not been subjected to sufficient clinical (and other) validation. As noted by the authors, research into an accepted and validated set of criteria is urgently needed.

“The finding that Problematic Smartphone Use was associated with depression, anxiety, and sleep difficulties, highlights the importance of further research to establish whether these relationships are potentially causally linked. I agree with the authors that longitudinal research is needed to help address this important issue.”


Dr Amy Orben, College Research Fellow at Emmanuel College and Research Fellow, MRC Cognition and Brain Sciences Unit, University of Cambridge, said:

“The review published today in BMC Psychiatry systematically collected studies on the topic of problematic smartphone behaviour to examine both the prevalence and effects of these behaviours in the teenage population. While the study press release states that the study provides an estimate that 1 in 4 children and young people are affected by problematic smartphone usage, I myself am cautious to draw these conclusions on the basis of the evidence provided. This is due to multiple concerns about the review’s methodology and inference I set out below.

“Firstly, the review included data from 41 studies, only 7% of which were longitudinal. The review itself highlights that all studies were of poor or moderate quality, with a high risk of bias, meaning that they are not a robust basis for wide-reaching conclusions. Meta-analyses and systematic reviews operate on a ‘Garbage In, Garbage Out’ principle: if the studies forming the basis of the review are low in quality the review itself will also be of low quality. As a colleague once put it – bad ingredients make bad soup. Furthermore, the review only included studies up to October 15th 2017 which is over 2 years ago. This means that the review is most probably missing many crucial studies published since then, making results out of date.

“Secondly, and of equal importance, is the lack of a consistent definition of problematic smartphone use in the review. In the 41 studies included, there were over 24 different and diverse definitions of problematic smartphone use. The authors averaged the prevalence of problematic smartphone use across all these 41 studies, without trying to take into account or match their many different definitions. By doing so they are likely to be comparing apples to oranges, especially as many measures of problematic smartphone use are poorly psychometrically validated and contested. This makes the conclusion that 1 in 4 children are affected by an undefined measure of problematic smartphone use very problematic in itself.

“Thirdly, a detailed outline of the search terms used when collecting the constituent studies included in this review was not available at time of writing this reaction. However, the overview of search terms in the main study seemed to show that the review included “behaviour, addictive” as a search term. This means that the review looked for studies that included the terms “behaviour” or “addictive” in their Medical Subject Headings. This should engender caution, as it makes it more likely that the review collected a biased sample of the literature. Studies that find addictive or problematic smartphone behaviour are more likely to state that in their title, abstract or text. Those studies that don’t find problematic smartphone behaviour, however, might fail to add such terminology into their study, as it is not important for their conclusions. This could lead to them not having “behaviour” or “addictive” in their Medical Subject Headings. As the review only collected those with these terms, it might be overlooking studies that did not find problematic smartphone use. This means that the study might be overestimating the prevalence of problematic smartphone usage.

“Lastly, it is important to note again that the vast majority of studies in this review (93%) where cross-sectional. This means that no causal statements can be made linking problematic smartphone use to outcomes like depression or suicide. It has been shown previously that smartphone effects are not a one-way street, but that mood can impact the amount of smartphone use as well, making these correlations bidirectional in nature.

“Overall, this study is a welcome addition to the literature which has been rapidly increasing in volume and is in need of careful synthesis. However, limits in its methodology means that the conclusions reached and relayed in the press release are uncertain and should be considered and replicated in other reviews before such results are taken as fact.”


‘Prevalence of problematic smartphone usage and associated mental health outcomes amongst children and young people: a systematic review, meta-analysis and GRADE of the evidence’ by Samantha Sohn et al. was published in BMC Psychiatry at 00:01 UK time on Friday 29th November. 

DOI: 10.1186/s12888-019-2350-x


Declared interests

Dr Sam Chamberlain: Dr Sam Chamberlain leads a Work Group as part of the European Network for Problematic Usage of the Internet (

Dr Amy Orben: No conflicts of interest

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