The relationship between screen time and mental health in young people: A systematic review of longitudinal studies

Probably not a substantial claim: may not pass S3 (load-bearing).

The most common internalising mental health symptoms were depression (n=23) and anxiety (n=10) followed by self-esteem (n=4).

“The most common internalising mental health symptoms were depression (n = 23) and anxiety (n = 10) followed by self-esteem (n = 4).”

May combine two claims.

The size of effects for the subset of articles examining total screen time and depression ranges from small to very small, with stronger associations for screen time to depression than the reverse.

“Based on these analyses, the size of the effects for this subset of articles ranges from small to very small, although with stronger associations for the relationship between screen time to depression, rather than the reverse”

May combine two claims.

Of nine studies examining television/video viewing and subsequent depressive symptoms, six found no association and three found a positive association.

“Of these, six studies found no association”

• Also stated in: § 3.3.2. Television/video · plain

  “while three studies reported that television/video viewing at baseline was positively associated with depressive symptoms at follow-up”

May combine two claims.

Of six studies examining videogame use and subsequent depressive symptoms, four reported no association, one reported a positive association, and one reported a negative association.

“Of these, four studies reported no association between videogame use at baseline and subsequent depressive symptoms”

• Also stated in: § 3.3.6. Videogames · plain

  “A fifth study reported that videogame use at baseline was positively associated with depressive symptoms at follow-up”

• Also stated in: § 3.3.6. Videogames · plain

  “while a sixth study reported that time spent playing games on the internet at baseline was negatively associated with depressive symptoms at follow-up”

May combine two claims. The quote only partly states this claim.

Of seven studies examining computer/internet use and subsequent depressive symptoms, three found no association, three found a positive association (one only among females, one only for weekend use), and one found no association for weekday use.

“Of these, three studies found no association between computer/internet use at baseline and subsequent depressive symptoms”

• Also stated in: § 3.3.3. Computer/internet · plain

  “Two studies found a positive association between computer/internet use at baseline and depressive symptoms at followup”

• Also stated in: § 3.3.3. Computer/internet · plain

  “A seventh study found no association between computer use on weekdays and subsequent depressive symptoms, and a small, positive association between weekend computer use and subsequent depressive symptoms”

May combine two claims.

Of four studies examining social media use and subsequent depressive symptoms, three reported no association and one found a small positive association for Instagram browsing.

“Three studies reported no association between social media use and subsequent depressive symptoms”

• Also stated in: § 3.3.5. Social media · plain

  “A fourth study found a small, positive association between the frequency of Instagram browsing and subsequent depressive symptoms”

Probably not a substantial claim: may not pass S3 (load-bearing).

Effect sizes were not able to be calculated for all studies due to wide variation in models fitted.

“Effect sizes were not able to be calculated for all studies due to wide variation in models fitted, in terms of types of models, the paths incorporated, and the way in which effects were reported.”

May combine two claims. The quote only partly states this claim.

Of three studies examining mobile phone use and subsequent depressive symptoms, two found a significant positive association and one found no association.

“Two studies found a significant positive association between mobile phone use and subsequent depressive symptoms”

• Also stated in: § 3.3.4. Mobile phone · plain

  “A third study found no association between daily time spent texting at baseline and subsequent depressive symptoms”

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In total, 17 studies examined the impact of screen time at baseline on subsequent level or change in mental health symptoms, 6 studies examined the impact of internalising mental health symptoms at baseline on subsequent screen time, and 12 studies examined bidirectional relationships.

“In total, 17 studies examined the impact of screen time at baseline on subsequent level or change in mental health symptoms, 6 studies examined the impact of internalising mental health symptoms at baseline on subsequent screen time, and 12 studies examined bidirectional relationships.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Seven studies examined other internalising symptoms.

“Seven studies examined other internalising symptoms, including general internalising or emotional problems and psychological wellbeing.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Many studies were conducted in the United States (14/35); sample sizes ranged from 126 to 12,866 participants; the majority (29/35) were generally evenly split between male and female participants.

“Many studies were conducted in the United States (14/ 35); sample sizes ranged from 126 to 12,866 participants; the majority (29/35) were generally evenly split between male and female participants.”

May combine two claims.

There was no significant association in either direction between social media use and subsequent anxiety, and anxiety and subsequent social media use.

“Both studies found no significant association in either direction.”

• cites Boers et al., 2020Not checked yet

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• cites Coyne et al., 2020 sourceNot checked yet

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The quote only partly states this claim.

There was no association between total screen time and subsequent internalising symptoms.

“Two studies found no association between total screen time and subsequent internalising symptoms (Allen & Vella, 2015;Perrino et al., 2019).”

• cites Allen & Vella, 2015 sourceNot checked yet

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• cites Perrino et al., 2019 sourceNot checked yet

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May combine two claims.

There was some evidence that self-esteem is positively associated with subsequent computer/internet use, negatively associated with subsequent videogame use, and not associated with subsequent mobile phone use.

“There was some evidence that self-esteem is positively associated with subsequent computer/internet use, negatively associated with subsequent videogame use, and not associated with subsequent mobile phone use.”

The quote only partly states this claim.

There was no association between television viewing and subsequent anxiety symptoms.

“Two studies found no association between television viewing and subsequent anxiety symptoms (Boers et al., 2020;Khouja et al., 2019).”

• cites Boers et al., 2020Not checked yet

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• cites Khouja et al., 2019 sourceNot checked yet

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Symptoms of Social Phobia and Generalised Anxiety Disorder, but not Panic Disorder, were positively associated with subsequent total screen time excluding television at follow-up in unadjusted models and in models adjusted for age, sex, race/ethnicity, SES, physical activity and BMI percentile.

“One study (Zink et al., 2019) found that symptoms of Social Phobia and Generalised Anxiety Disorder, but not Panic Disorder, were positively associated with subsequent total screen time (excluding television) at follow-up in unadjusted models, and in models adjusted for age, sex, race/ethnicity, SES, physical activity and BMI percentile.”

• cites Zink et al., 2019 sourceNot checked yet

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Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing). The quote only partly states this claim.

There was no association between mobile phone use and subsequent anxiety symptoms.

“One study reported no association between these variables (Khouja et al., 2019)”

• cites Khouja et al., 2019 sourceNot checked yet

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Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing). The quote only partly states this claim.

There was no association between videogame use and subsequent anxiety symptoms.

“One study reported no association between videogame use, and subsequent anxiety symptoms (Boers et al., 2020)”

• cites Boers et al., 2020Not checked yet

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May combine two claims.

Adjusted models were smaller and non-significant for symptoms specific to Panic Disorder.

“Adjusted models were smaller and non-significant for symptoms specific to Panic Disorder.”

• cites Zink et al., 2019 sourceNot checked yet

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There were no significant associations between television viewing and subsequent Generalised Anxiety Disorder or Social Phobia symptoms in unadjusted models, and a small, negative association between television viewing and subsequent Social Phobia symptoms in adjusted models.

“There were no significant associations between television viewing, and subsequent Generalised Anxiety Disorder or Social Phobia symptoms in unadjusted models, and a small, negative association between television viewing and subsequent Social Phobia symptoms in adjusted models.”

• cites Zink et al., 2019 sourceNot checked yet

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The association between time spent playing videogames and subsequent anxiety symptoms was positive for females, but negative for males.

“while the second study reported that the association between time spent playing videogames and subsequent anxiety symptoms was positive for females, but negative for males (Ohannessian, 2018).”

• cites Ohannessian, 2018 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

The duration of follow-up across studies ranged from six months to 12 years.

“The duration of follow-up across studies ranged from six months to 12 years.”

May combine two claims.

Evidence regarding the association between anxiety and subsequent total screen time was mixed, with one study reporting no association and a second reporting a positive association.

“Evidence regarding the association between anxiety and subsequent total screen time was mixed, with one study reporting no association between these variables, and a second study reporting a positive association between these variables.”

May combine two claims.

The evidence on sex differences was largely inconsistent as to the direction, and medium type, but nevertheless was apparent across the body of work.

“However, the evidence was largely inconsistent as to the direction, and medium type, but nevertheless was apparent across the body of work.”

May combine two claims.

There was some evidence of positive associations between both computer/internet and mobile phone use and subsequent depression, but little evidence of positive associations between television or videogame use, and subsequent depression or other internalising problems.

“For instance, while there was some evidence of positive associations between both computer/internet and mobile phone use and subsequent depression, there was little evidence of positive associations between television or videogame use, and subsequent depression or other internalising problems.”

May combine two claims.

The relationship between screen time and depressive symptoms varied between different types of screen devices and uses, with stronger relationships seen for newer forms of technology, such as mobile phones and computer/internet, compared to older technologies, such as television and videogames.

“the relationship between screen time and depressive symptoms varied between different types of screen devices and uses, with stronger relationships seen for newer forms of technology, such as mobile phones and computer/internet, compared to older technologies, such as television and videogames.”

May combine two claims.

There was no association between television viewing at baseline and both internalising symptoms and psychological wellbeing at follow-up.

“The authors found no association between television viewing at baseline and both internalising symptoms and psychological wellbeing at follow-up.”

• cites Poulain et al., 2019 sourceNot checked yet

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There was no association between mobile phone use at baseline and internalising symptoms at follow-up, and a negative association between mobile phone use at baseline and psychological well-being at follow-up.

“This study found no association between mobile phone use at baseline and internalising symptoms at follow-up, and a negative association between mobile phone use at baseline and psychological well-being at follow-up.”

• cites Poulain et al., 2019 sourceNot checked yet

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The relationship between screen time and subsequent depression, although only small to very small in size, was stronger than the reverse relationship between depression and subsequent screen time.

“the relationship between screen time and subsequent depression, although only small to very small in size, was stronger than the reverse relationship between depression and subsequent screen time;”

Probably not a substantial claim: may not pass S3 (load-bearing).

In the current review, the nature and comprehensiveness of the analyses performed and reported varied widely between studies.

“In the current review, we found that the nature and comprehensiveness of the analyses performed and reported varied widely between studies.”

May combine two claims.

Social media appeared to be positively associated with subsequent internalising problems and psychological distress; however, the relationship between social media and psychological distress may be more pronounced among females compared to males.

“Social media appeared to be positively associated with subsequent internalising problems and psychological distress; however, the relationship between social media and psychological distress may be more pronounced among females compared to males.”

May combine two claims.

There was a positive association between computer/internet use at baseline and internalising symptoms at follow-up, and a negative association between computer/internet use at baseline and psychological well-being at follow-up.

“The authors reported a positive association between computer/internet use at baseline and internalising symptoms at follow-up, and a negative association between computer/internet use at baseline and psychological well-being at follow-up.”

• cites Poulain et al., 2019 sourceNot checked yet

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The majority of studies examined the longitudinal relationship between screen time and depressive symptoms; there were relatively few studies examining the relationship between screen time and anxiety, self-esteem, and other internalising symptoms.

“Fourth, the majority of studies examined the longitudinal relationship between screen time and depressive symptoms; there were relatively few studies examining the relationship between screen time and anxiety, self-esteem, and other internalising symptoms.”

May combine two claims.

Some studies only included passive or sedentary screen use in their definition of screen time, while others included both active and passive screen use.

“For instance, some studies only included passive or sedentary screen use in their definition of screen time (e.g., Houghton et al., 2018), while others included both active and passive screen use.”

• cites Houghton et al., 2018 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

Inter-rater agreement for full-text assessment was high (κ = 0.82).

“All retained full-text articles were assessed by ST and AWS for inclusion (κ = 0.82).”

May combine two claims.

Quantitative synthesis of studies was judged impractical and potentially misleading due to the diversity of types of outcomes and models.

“As a consequence of the diversity of types of outcomes and models, we judged that quantitative synthesis of studies was impractical and potentially misleading.”

May combine two claims.

Adjustment by variables that play other causal roles (mediators, moderators, outcomes) can have uncertain effects, and may obscure effects or result in overestimation.

“However, adjustment by variables that play other causal roles, either as mediators, moderators or outcomes can have uncertain effects, and may obscure effects or result in overestimation.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

An increase in the prevalence of mental health problems and suicide among young people has been reported in other countries.

“An increase in the prevalence of mental health problems and suicide among young people has also been reported in other countries (Padmanathan, Bould, Winstone, Moran, & Gunnell, 2020;Pitchforth et al., 2018;Thorisdottir, Asgeirsdottir, Sigurvinsdottir, Allegrante, & Sigfusdottir, 2017;Wiens et al., 2020).”

• cites Padmanathan et al., 2020 sourceNot checked yet

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• cites Pitchforth et al., 2018 sourceNot checked yet

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• cites Thorisdottir et al., 2017 sourceNot checked yet

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Classified as probably not a substantial claim.

Positive associations between screen time and mental health problems, including depressive symptoms and suicidality, have been reported.

“Positive associations between screen time and mental health problems, including depressive symptoms and suicidality, having been reported (Twenge et al., 2018).”

• cites Twenge et al., 2018 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

Inter-rater agreement for title/abstract screening was high (κ = 0.91).

“Agreement was high between the two authors (κ = 0.91).”

Probably not a substantial claim: may not pass S3 (load-bearing).

Quality assessment was conducted independently by two authors.

“Assessment was conducted independently by ST and AWS and discrepancies were resolved through discussion.”

Probably not a substantial claim: may not pass S3 (load-bearing).

The protocol was registered with PROSPERO (CRD42020180145).

“The protocol was registered with PROSPERO (registration number CRD42020180145).”

Probably not a substantial claim: may not pass S3 (load-bearing).

A recent US study found that screen time accounted for only 0.4% of variation in mental wellbeing in an adolescent population.

“For instance, a recent study conducted in the United States found that screen time accounted for only 0.4% of variation in mental wellbeing in an adolescent population (Orben & Przybylski, 2019).”

• cites Orben & Przybylski, 2019 sourceNot checked yet

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May combine two claims.

Comprehensive inclusion of confounders can lead to less biased estimates of the causal effect of screen time on mental health and vice versa.

“Comprehensive inclusion of confoundersvariables that drive both mental health and screen timecan lead to less biased estimates of the causal effect of screen time on mental health and vice versa.”

Probably not a substantial claim: may not pass S4 (based). May combine two claims.

Omission of paths reflecting previous mental health and screen time status or modelling change in status using growth curves or change scores can inflate estimates, while their inclusion can improve precision and reduce bias.

“Omission of paths reflecting previous mental health and screen time status or modelling change in status using growth curves or changes scores (paths c and d respectively) can inflate estimates while their inclusion can improve precision and reduce bias.”

Classified as probably not a substantial claim. May combine two claims.

A systematic review of 13 published reviews concluded that there is moderately strong evidence for a positive association between screen time and depressive symptoms in children and adolescents, but not for behavior problems, anxiety, hyperactivity and inattention, self-esteem, well-being, and psychosocial health.

“A systematic review of 13 published reviews concluded that there is moderately strong evidence for a positive association between screen time and depressive symptoms in children and adolescents, but not behavior problems, anxiety, hyperactivity and inattention, self-esteem, well-being, and psychosocial health (Stiglic & Viner, 2019).”

• cites Stiglic & Viner, 2019 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Between 2010 and 2015, there was a 33% increase in US adolescents with high depressive symptoms and a 31% increase in adolescent suicide deaths.

“Between 2010 and 2015, a 33% increase in the number of adolescents exhibiting high levels of depressive symptoms, and a 31% increase in adolescent suicide deaths was observed in the United States (Twenge, Cooper, Joiner, Duffy, & Binau, 2019).”

• cites Twenge et al., 2019Not checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

The review followed PRISMA guidelines for reporting.

“We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (Moher, Liberati, Tetzlaff, Altman, & Group, 2009) for reporting this systematic review.”

• cites Moher et al., 2009 sourceNot checked yet

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Longitudinal studies provide more robust data because they can examine correlations over time and provide insight into the direction of observed effects.

“Longitudinal studies provide more robust data because they can examine correlations over time and provide insight into the direction of observed effects.”

Classified as probably not a substantial claim.

Omission of confounding variables can result in overestimation of effects.

“Conversely, omission of confounding variables can result in overestimation of effects.”

May combine two claims.

All, or almost all, studies provided exact information on follow-up duration, non-selective reporting of results, a clear description of their statistical approach, and point estimates and measures of variability.

“All, or almost all, studies provided exact information on follow-up duration (100%), non-selective reporting of results (97.1%), a clear description of their statistical approach (94.3%), and point estimates and measures of variability (88.6%).”

May combine two claims.

Variation in the relationship between screen time and depression according to screen device type or use indicates that screen time in itself is unlikely to causally increase mental health problems; rather, the relationship between screen time and mental health problems is likely dependent on screen content and activity.

“Variation in the relationship between screen time and depression according to screen device type or use indicate that screen time in itself is unlikely to causally increase mental health problems; rather, it is likely that the relationship between screen time and mental health problems is dependent on screen content and activity.”

May combine two claims.

The results of the current review largely align with past systematic reviews, which have concluded that there is a positive association between screen time and depressive symptoms, and a weak association between screen time and both anxiety and self-esteem.

“The results of the current review largely align with past systematic reviews, which have concluded that there is a positive association between screen time and depressive symptoms (Hoare et al., 2016;Liu et al., 2016;Stiglic & Viner, 2019;Wang et al., 2019), and a weak association between screen time and both anxiety and self-esteem (Stiglic & Viner, 2019).”

• cites Hoare et al., 2016 sourceNot checked yet

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• cites Stiglic & Viner, 2019 sourceNot checked yet

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• cites Wang et al., 2019 sourceNot checked yet

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Use of social media for the purpose of social comparison and feedback seeking, and passive rather than active use of social media, have been shown to be associated with higher subsequent depressive symptoms among adolescents.

“Furthermore, the use of social media for the purpose of social comparison and feedback seeking (Nesi & Prinstein, 2015), and passive, rather than active use of social media (Frison & Eggermont, 2016;Thorisdottir, Sigurvinsdottir, Asgeirsdottir, Allegrante, & Sigfusdottir, 2019) have been shown to be associated with higher subsequent depressive symptoms among adolescents.”

• cites Nesi & Prinstein, 2015 sourceNot checked yet

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• cites Frison & Eggermont, 2016 sourceNot checked yet

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• cites Thorisdottir et al., 2019 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

Past systematic reviews have concluded that social media is positively associated with depression, anxiety and psychological distress in adolescents.

“Past systematic reviews have concluded that social media is positively associated with depression, anxiety and psychological distress in adolescents (Keles et al., 2020;McCrae et al., 2017).”

• cites Keles et al., 2020 sourceNot checked yet

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• cites McCrae et al., 2017 sourceNot checked yet

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Probably not a substantial claim: may not pass S4 (based).

The current review is the first to provide a comprehensive overview of research examining the bidirectional, longitudinal relationship between screen time and internalising mental health symptoms in young people.

“The current review is the first to provide a comprehensive overview of research examining the bidirectional, longitudinal relationship between screen time and internalising mental health symptoms in young people.”

May combine two claims.

Most studies used a validated measure of mental health symptoms in its original form, provided exact sample size at each measurement, and provided adequate description of the sampling and recruitment methods.

“Most studies used a validated measure of mental health symptoms in its original form (82.9%), provided exact sample size at each measurement (68.6%), and provided adequate description of the sampling and recruitment methods (62.9%).”

May combine two claims.

The relationship between total screen time and subsequent depressive symptoms was stronger than the relationship between depressive symptoms and subsequent screen time, which provides partial support for the hypothesis that greater screen time is associated with increases in internalising mental health problems.

“We found that the relationship between total screen time and subsequent depressive symptoms was stronger than the relationship between depressive symptoms and subsequent screen time, which provides partial support for the hypothesis that greater screen time is associated with increases in internalising mental health problems.”

Probably not a substantial claim: may not pass S3 (load-bearing).

These findings are consistent with the results of a recent systematic review, which concluded that screen type is a significant moderator of the relationship between screen time and internalising mental health symptoms.

“These findings are consistent with the results of a recent systematic review, which concluded that screen type is a significant moderator of the relationship between screen time and internalising mental health symptoms (Zink, Belcher, et al., 2020).”

• cites Zink, Belcher, et al., 2020Not checked yet

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May combine two claims.

Social media use may be associated with higher levels of loneliness among adolescents who are already low in in-person social interaction, but not those high in in-person social interaction.

“For instance, it has been shown that social media use may be associated with higher levels of loneliness among adolescents who are already low in in-person social interaction, but not those high in in-person social interaction (Twenge, Spitzberg, & Campbell, 2019).”

• cites Twenge, Spitzberg, & Campbell, 2019Not checked yet

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Overadjustment through inclusion of covariates that are not confounders risks biasing parameter estimates and, in some analyses, may have also introduced high levels of multi-collinearity.

“The latter risks biasing parameter estimates and, in some analyses, may have also introduced high levels of multi-collinearity.”

May combine two claims.

The existence of an association between depressive symptoms and subsequent screen time cannot be ruled out, particularly given that studies utilising appropriate, sophisticated statistical methods reported bidirectional associations between screen time and depressive symptoms.

“However, we are unable to rule out the existence of this association, particularly given that studies utilising appropriate, sophisticated statistical methods, such as that of Houghton et al. (2018), reported bidirectional associations between screen time and depressive symptoms.”

• cites Houghton et al. (2018) sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Other studies reported non-significant associations between total screen time and depression, implying that the effect size confidence intervals include zero.

“Other studies reported non-significant associations between total screen time and depression, implying that the effect size confidence intervals include zero.”

May combine two claims.

Limitations included the use of models where the omission of certain paths may have biased estimates of effect in either direction, and overadjustment through the inclusion of covariates that are not confounders.

“Limitations included the use of models where the omission of certain paths may have biased estimates of effect in either direction, and overadjustment through the inclusion of covariates that are not confounders.”

May combine two claims.

All included studies utilised self-report or parent-reported measures of both screen time and mental health outcomes; no studies meeting the inclusion criteria utilised clinician-rated measures of mental health, and only one study utilised EMA to measure screen time.

“First, all included studies utilised self-report or parent-reported measures of both screen time and mental health outcomes; no studies meeting the inclusion criteria utilised clinician-rated measures of mental health, and only one study utilised EMA to measure screen time (Bickham et al., 2015).”

• cites Bickham et al., 2015 sourceNot checked yet

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Screens enable young people to connect with others and to access mental health information and support.

“For instance, screens enable young people to connect with others and to access mental health information and support (Horgan & Sweeney, 2010).”

• cites Horgan & Sweeney, 2010Not checked yet

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May combine two claims.

There was variation between studies in the definition of screen time, and self-report measures used to assess screen time.

“Second, there was variation between studies in the definition of 'screen time', and self-report measures used to assess screen time.”

Probably not a substantial claim: may not pass S3 (load-bearing).

The funders had no role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication.

“The funders had no role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication.”

May combine two claims.

The procedural quality of studies included in the current review varied widely, with the majority of studies not providing information about whether participants who dropped out from the study differed from those who remained in the study, and about participation rates at baseline, making it difficult to assess whether their results were subject to bias.

“Finally, the procedural quality of studies included in the current review varied widely, with the majority of studies not providing information about whether participants who dropped out from the study differed from those who remained in the study, and about participation rates at baseline, making it difficult to assess whether their results were subject to bias.”

May combine two claims.

The current review suggests that public discourse on screen time may not accurately reflect the available scientific literature, and that the magnitude of the effects when they can be measured range from small to very small.

“The current review suggests that this discourse may not accurately reflect the available scientific literature, and that the magnitude of the effects when they can be measured range from small to very small.”