Social Media Use and Mental Health and Well-Being Among Adolescents – A Scoping Review

Introduction: Social media has become an integrated part of daily life, with an estimated 3 billion social media users worldwide. Adolescents and young adults are the most active users of social media. Research on social media has grown rapidly, with the potential association of social media use and mental health and well-being becoming a polarized and much-studied subject. The current body of knowledge on this theme is complex and difficult-to-follow. The current paper presents a scoping review of the published literature in the research field of social media use and its association with mental health and well-being among adolescents. Methods and Analysis: First, relevant databases were searched for eligible studies with a vast range of relevant search terms for social media use and mental health and well-being over the past five years. Identified studies were screened thoroughly and included or excluded based on prior established criteria. Data from the included studies were extracted and summarized according to the previously published study protocol. Results: Among the 79 studies that met our inclusion criteria, the vast majority (94%) were quantitative, with a cross-sectional design (57%) being the most common study design. Several studies focused on different aspects of mental health, with depression (29%) being the most studied aspect. Almost half of the included studies focused on use of non-specified social network sites (43%). Of specified social media, Facebook (39%) was the most studied social network site. The most used approach to measuring social media use was frequency and duration (56%). Participants of both genders were included in most studies (92%) but seldom examined as an explanatory variable. 77% of the included studies had social media use as the independent variable. Conclusion: The findings from the current scoping review revealed that about 3/4 of the included studies focused on social media and some aspect of pathology. Focus on the potential association between social media use and positive outcomes seems to be rarer in the current literature. Amongst the included studies, few separated between different forms of (inter)actions on social media, which are likely to be differentially associated with mental health and well-being outcomes.


BACKGROUND
In just a few decades, the use of social media have permeated most areas of our society. For adolescents, social media play a particularly large part in their lives as indicated by their extensive use of several different social media platforms (Ofcom, 2018). Furthermore, the use of social media and types of platforms offered have increased at such a speed that there is reason to believe that scientific knowledge about social media in relation to adolescents' health and well-being is scattered and incomplete (Orben, 2020). Nevertheless, research findings indicating the potential negative effects of social media on mental health and well-being are frequently reported in traditional media (newspapers, radio, TV) (Bell et al., 2015). Within the scientific community, however, there are ongoing debates regarding the impact and relevance of social media in relation to mental health and well-being. For instance, Twenge and Campbell (2019) stated that use of digital technology and social media have a negative impact on well-being, while  argued that the association between digital technology use and adolescent well-being is so small that it is more or less inconsequential. Research on social media use is a new focus area, and it is therefore important to get an overview of the studies performed to date, and describe the subject matter studies have investigated in relation to the effect of social media use on adolescents mental health and well-being. Also, research gaps in this emerging research field is important to highlight as it may guide future research in new and meritorious directions. A scoping review is therefore deemed necessary to provide a foundation for further research, which in time will provide a knowledge base for policymaking and service delivery.
This scoping review will help provide an overall understanding of the main foci of research within the field of social media and mental health and well-being among adolescents, as well as the type of data sources and research instruments used so far. Furthermore, we aim to highlight potential gaps in the research literature (Arksey and O'Malley, 2005). Even though a large number of studies on social media use and mental health with different vantage points has been conducted over the last decade, we are not aware of any broad-sweeping scoping review covering this area.

AIMS
This scoping review aims to give an overview of the main research questions that have been focused on with regard to use of social media among adolescents in relation to mental health and wellbeing. Both quantitative and qualitative studies are of interest. Three specific secondary research questions will be addressed and together with the main research question serve as a template for organizing the results: • Which aspects of mental health and well-being have been the focus or foci of research so far? • Has the research focused on different research aims across gender, ethnicity, socio-economic status, geographic location? What kind of findings are reported across these groups? • Organize and describe the main sources of evidence related to social media that have been used in the studies identified.

DEFINING ADOLESCENCE AND SOCIAL MEDIA
In the present review, adolescents are defined as those between 13 and 19 years of age. We chose the mean age of 13 as our lower limit as nearly all social media services require users to be at least 13 years of age to access and use their services (Childnet International, 2018). All pertinent studies which present results relevant for this age range is within the scope of this review. For social media we used the following definition by Kietzmann et al. (2011, p. 1): "Social media employ mobile and webbased technologies to create highly interactive platforms via which individuals and communities share, co-create, discuss, and modify user-generated content." We also employed the typology described by Kaplan and Haenlein's classification scheme across two axes: level of self-presentation and social presence/media richness (Kaplan and Haenlein, 2010). The current scoping review adheres to guidelines and recommendations stated by Tricco et al. (2018). See protocol for further details about the definitions used (Schønning et al., 2020).

DATA SOURCES AND SEARCH STRATEGY
A literature search was performed in OVID Medline, OVID Embase, OVID PsycINFO, Sociological Abstracts (proquest), Social Services Abstracts (proquest), ERIC (proquest), and CINAHL. The search strategy combined search terms for adolescents, social media and mental health or wellbeing. The database-controlled vocabulary was used for searching subject headings, and a large spectrum of synonyms with appropriate truncations was used for searching title, abstract, and author keywords. A filter for observational studies was applied to limit the results. The search was also limited to publications from 2014 to current. The search strategy was translated between each database. An example of full strategy for Embase is attached as Supplementary Material.

STUDY SELECTION: EXCLUSION AND INCLUSION CRITERIA
The exclusion and inclusion criteria are detailed in the protocol (Schønning et al., 2020). Briefly, we included English language peer-reviewed quantitative-or qualitative papers or systematic reviews published within the last 5 years with an explicit focus on mental health/well-being and social media. Non-empirical studies, intervention studies, clinical studies and publications not peer-reviewed were excluded. Intervention studies and clinical studies were excluded as we sought to not introduce too much heterogeneity in design and our focus was on observational studies. The criteria used for study selection was part of an iterative process which was described in detail in the protocol (Schønning et al., 2020). As per the study protocol (Schønning et al., 2020), and in line with scoping review guidelines (Peters et al., 2015(Peters et al., , 2017Tricco et al., 2018), we did not assess methodological quality or risk of bias of the included studies.
The selection process is illustrated by a flow-chart indicating the stages from unsorted search results to the number of included studies (see Figure 1). Study selection was accomplished and organized using the Rayyan QCRI software 1 . The inclusion and exclusion process was performed independently by VS and JCS. The interrater agreement was κ = 0.87, indicating satisfactory agreement. 1 https://rayyan.qcri.org/welcome

DATA EXTRACTION AND ORGANIZATION
Details of the data extracted is described in the protocol. Three types of information were extracted, bibliographic information, information about study design and subject matter information. Subject matter information included aim of study, how social media and mental health/well-being was measured, and main findings of the study.

Visualization of Words From the Titles of the Included Studies
The most frequently occurring words and bigrams in the titles of the included studies are presented in Figures 2, 3. The following procedure was used to generate Figure 1: First, a text file containing all titles were imported into R FIGURE 2 | Word cloud from the titles of the included studies. Most frequent words, excluding variations of "adolescence" and "social media." N = 113. Shades of blue indicate word frequencies >2 and green a frequency of 2. The size of each word is indicative of its relative frequency of occurrence.
as a data frame (R Core Team, 2014). The data frame was processed using the "tidy text"-package with required additional packages (Silge and Robinson, 2016). Second, numbers and commonly used words with little inherent meaning (so called "stop words, " such as "and, " "of, " and "in"), were removed from the data frame using the three available lexicons in the "tidy-text"-package (Silge and Robinson, 2016). Furthermore, variations of "adolescents" (e.g., "adolescent, " "adolescence, " and "adolescents") and "social media" (e.g., "social media, " "social networking, " "online social networks") were removed from the data frame. Third, the resulting data frame was sorted based on frequency of unique words, and words occurring only once were removed. The final data frame is presented as a word cloud in Figure 1 (N = 113). The same procedure as described above was employed to generate commonly occurring bigrams (two words occurring adjacent to each other), but without removing bigrams occurring only once (N = 231). The word clouds were generated using the "wordcloud2"-package in R (Lang and Chien, 2018). For Figure 1, shades of blue indicate word frequencies >2 and green a frequency of 2. For Figure 2, shades of blue indicate bigram frequencies of >1 and green a frequency of 1.
Five studies had a specific and sole focus on the link between social media use and alcohol, and examined how various alcoholrelated social media use affected alcohol intake Beullens, 2017, 2018;Nesi et al., 2017b;Critchlow et al., 2019). Some studies had a more theory-based focus and investigated themes such as peer comparison, social media intrusion or pro-social behavior on social media and its effect on mental health Rousseau et al., 2017;de Lenne et al., 2018). One of the included studies looked into night-time specific social media use  and one looked into pre-bedtime social media behavior  to study the link between this use and sleep.

Cyberbullying as a Nexus
Thirteen of the 79 (17%) included studies investigated cyberbullying as the measurement of social media use Cross et al., 2015;Hamm et al., 2015;Hase et al., 2015;Spears et al., 2015;Fahy et al., 2016;Fisher et al., 2016;Foody et al., 2017;Przybylski and Bowes, 2017;Wolke et al., 2017;Fredrick and Demaray, 2018;John et al., 2018;Holfeld and Mishna, 2019). Most of the systematic reviews and meta-analyses included focused on cyberbullying. A cross-sectional study from 2017 suggests that cyberbullying has similar negative effects as direct or relational bullying, and that cyberbullying is "mainly a new tool to harm victims already bullied by traditional means" . A metaanalysis from 2016 concludes that "peer cybervictimization is indeed associated with a variety of internalizing and externalizing problems among adolescents" . A systematic review from 2018 concludes that both victims and perpetrators of cyberbullying are at greater risk of suicidal behavior compared with non-victims and non-perpetrators .

Strengths and Limitations of Present Study
The main strength of this scoping review lies in the effort to give a broad overview of published research related to use of social media, and mental health and well-being among adolescents. Although a range of reviews on screen-based activities in general and mental health and well-being exist (Dickson et al., 2018;Orben, 2020), they do not necessarily discern between social media use and other types of technology-based media. Also, some previous reviews tend to be more particular regarding mental health outcome (Best et al., 2014;Seabrook et al., 2016;Orben, 2020), or do not focus on adolescents per se (Seabrook et al., 2016). The main limitation is that, despite efforts to make the search strategy as comprehensive and inclusive as possible, we probably have not been able to identify all relevant studies -this is perhaps especially true when studies do include relevant information about social media and mental health/well-being, but this information is part of sub-group analyses or otherwise not the main aim of the studies. In a similar manner, related to qualitative studies, we do not know if our search strategy were as efficient in identifying studies of relevance if this was not the main theme or focus of the study. Despite this, we believe that we were able to strike a balance between specificity and sensitivity in our search strategy.

Description of Central Themes and Core Concepts
The findings from the present scoping review on social media use and mental health and well-being among adolescents revealed that the majority (about 3/4) of the included studies focused on social media and pathology. The core concepts identified are social media use and its statistical association with symptoms of depression, general psychiatric symptoms and other symptoms of psychopathology. Similar findings were made by Keles et al. (2020) in a systematic review from 2019. Focus on the potential association between social media use and positive outcomes seems to be rarer in the current literature, even though some studies focused on well-being which also includes positive aspects of mental health. Studies focusing on screen-based media in general and well-being is more prevalent than studies linking social media specifically with well-being (Orben, 2020). The notion that excessive social media use is associated with poor mental health is well established within mainstream media. Our observation that this preconception seems to be the starting point for much research is not conducive to increased knowledge, but also alluded to elsewhere (Coyne et al., 2020).

Why the Focus on Poor Mental Health/Pathology?
The relationship between social media and mental health is likely to be complex, and social media use can be beneficial for maintaining friendships and enriching social life (Seabrook et al., 2016;Birkjaer and Kaats, 2019;Coyne et al., 2020;Orben, 2020). This scoping review reveals that the majority of studies focusing on effects of social media use has a clearly stated focus on pathology and detrimental results of social media use. Mainstream media and the public discourse has contributed in creating a culture of fear around social media, with a focus on its negative elements (Ahn, 2012;O'Reilly et al., 2018). It is difficult to pin-point why the one-sided focus on the negative effects of social media has been established within the research literature. But likely reasons are elements of "moral panic, " and reports of increases in mental health problems among adolescents in the same period that social media were introduced and became widespread (Birkjaer and Kaats, 2019). The phenomenon of moral panic typically resurges with the introduction and increasing use of new technologies, as happened with video games, TV, and radio (Mueller, 2019).

The Metrics of Social Media
Social media trends change rapidly, and it is challenging for the research field to keep up. The included studies covered some of the most frequently used social media, but the amount of studies focusing on each social media did not accurately reflect the contemporary distribution of users. Even though sites such as Instagram and Snapchat were covered in some studies, the coverage did not do justice to the amount of users these sites had. Newer social media sites such as TikTok were not mentioned in the included studies even though it has several hundred million daily users (Mediakix, 2019;Wallaroo, 2020).
Across the included studies there was some variation in how social media were gauged, but the majority of studies focused on the mere frequency and duration of use. There were little focus on separating between different forms of (inter)actions on social media, as these can vary between being a victim of cyberbullying to participating in healthy community work. Also, few studies differentiated between types of actions (i.e., posting, scrolling, reading), active and passive modes of social media use (i.e., production versus consumption, and level of interactivity), a finding similar to other reports (Seabrook et al., 2016;Verduyn et al., 2017;Orben, 2020). There is reason to believe that different modes of use on social media platforms are differentially associated with mental health, and a recent narrative review highlight the need to address this in future research (Orben, 2020). One of the included studies found for instance that it is not the total time spent on Facebook or the internet, but the specific amount of time allocated to photo-related activities that is associated with greater symptoms of eating disorders such as thin ideal internalization, selfobjectification, weight dissatisfaction, and drive for thinness (Meier and Gray, 2014). This observation can possibly be explained by social comparison mechanisms (Appel et al., 2016) and passive use of social media (Verduyn et al., 2017). The lack of research differentiating social media use and its association with mental health is an important finding of this scoping review and will hopefully contribute to this being included in future studies.
Few studies examined the motivation behind choosing to use social media, or the mental health status of the users when beginning a social media session. It has been reported that young people sometimes choose to enter sites such as Facebook and Twitter as an escape from threats to their mental health such as experiencing overwhelming pressure in daily life (Boyd, 2014). This kind of escapism can be explained through uses and gratifications theory [see for instance (Coyne et al., 2020)]. On the other hand, more recent research suggest that additional motivational factors may include the need to control relationships, content, presentation, and impressions , and it is possible that social media use can act as an reinforcement of adolescents' current moods and motivations (Birkjaer and Kaats, 2019). Regardless, it seems obvious that the interplay between online and offline use and underlying motivational mechanisms needs to be better understood.
There has also been some questions about the accuracy when it comes to deciding the amount and frequency of one's personal social media use. Without measuring duration and frequency of use directly and objectively it is unlikely that subjective self-report of general use is reliable (Kobayashi and Boase, 2012;Scharkow, 2016Scharkow, , 2019Naab et al., 2019). Especially since the potential for social media use is almost omnipresent and the use itself is diverse in nature. Also, due to processes such as social desirability, it is likely that some participants report lower amounts of social media use as excessive use is seen largely undesirable (Krumpal, 2013). Inaccurate reporting of prior social media use could also be a threat to the validity of the reported numbers and thus bias the results reported. Real-time tracking of actual use and modes of use is therefore recommended in future studies to ensure higher accuracy of these aspects of social media use (Coyne et al., 2020;Orben, 2020), despite obvious legal and ethical challenges. Another aspect of social media use which does not seem to be addressed is potential spill-over effects, where use of social media leads to potential interest in or thinking about use ofand events or contents on -social media when the individual is offline. When this aspect has been addressed, it seems to be in relation to preoccupations and with a focus on excessive use or addictive behaviors (Griffiths et al., 2014). Conversely, given the ubiquitous and important role of social media, experiences on social media -for better or for worse -are likely to be interconnected with the rest of an individual's lived experience (Birkjaer and Kaats, 2019).
The Studies Seem to Implicitly Think That the Use of Social Media "Causes"/"Affects" Mental Health (Problems) Most of the included studies establish an implicit causation between social media and mental health. It is assumed that social media use has an impact on mental health. The majority of studies included establish some correlation between more frequent use of social media and poor well-being/mental health, as evident from Supplementary Table 2. As formerly mentioned, most of the included studies are cross-sectional and cannot shed light into temporality or cause-and-effect. In total, only 16 studies had a longitudinal design, using different types of regression models, latent growth curve models and cross-lagged models. Yet there seems to be an unspoken expectation that the direction of the association is social media use affecting mental health. The reason for this supposition is unclear, but again it is likely that the mainstream media discourse dominated by mostly negative stories and reports of social media use has some impact together with the observed moral panic.
With the increased popularity of social media and internet arrived a reduction of face-to-face contact and supposed increased social isolation (Kraut et al., 1998;Espinoza and Juvonen, 2011). This view is described as the displacement hypothesis [see for instance (Coyne et al., 2020)]. Having a thriving social life and community with meaningful relations are for many considered vital for well-being and good mental health, and the supposed reduction of sociality were undoubtedly met with skepticism by some. Social media use has increased rapidly among young people over the last two decades along with reports that mental health problems are increasing. Several studies report that there is a rising prevalence of symptom of anxiety and depression among our adolescents (Bor et al., 2014;Olfson et al., 2015). The observation that increases in social media use and mental health issues happened in more or less the same time period can have contributed to focus on how use of social media affects mental health problems.
The existence of an implicit causation is supported by the study variables chosen and the lack of positively worded outcomes. Depression, anxiety, alcohol use, psychiatric problems, suicidal behavior and eating disorders are amongst the most studied outcome-variables. On the other side of the spectrum we have well-being, which can oscillate from positive to negative, whilst the measures of pathology only vary from "ill" to "not ill" with positive outcomes not possible.
What Is the Gap in the Literature?
The current literature on social media and mental health among youth is still developing and has several gaps and shortcomings, as evident from this scoping review and other publications (Seabrook et al., 2016;Coyne et al., 2020;Keles et al., 2020;Orben, 2020). Some of the gaps and shortcomings in the field we propose solutions for has been identified in a systematic review from 2019 by Keles et al. (2020). The majority of the included studies in the current scoping review were cross-sectional, were limited in their inclusion of potential confounders and 3rd variables such as sociodemographics and personality, preventing knowledge about possible cause-and-effect between social media and mental health. There is a lack of longitudinal studies examining the effects of social media over extended periods of time, as well as investigations longitudinally of how mental health impacts social media use. However, since the formal search was ended for this scoping review, some innovative studies have emerged using longitudinal data (Brunborg and Andreas, 2019;Coyne et al., 2020). More high quality longitudinal studies of social media use and mental health could help us identify the patterns over time and help us learn about possible cause-and-effect relationships, as well as disentangling between-and within-person associations (Coyne et al., 2020;Orben, 2020). Furthermore, both social media use and mental health are complex phenomena in themselves, and future studies need to consider which aspects they want to investigate when trying to understand their relationship. Mechanisms linking social media use and eating disorders are for instance likely to be different than mechanisms linking social media use and symptoms of ADHD.
Our literature search also revealed a paucity of qualitative studies exploring the why's and how's of social media use in relation to mental health among adolescents. Few studies examine how youth themselves experience and perceive the relationship between social media and mental health, and the reasons for their continued and frequent use. Qualitatively oriented studies would contribute to a deeper understanding of adolescent's social media sphere, and their thoughts about the relationship between social media use and mental health [see for instance ]. For instance, O'Reilly et al. (2018) found that adolescents viewed social media as a threat to mental well-being, and concluded that they buy into the idea that "inherently social media has negative effects on mental wellbeing" and seem to "reify the moral panic that has become endemic to contemporary discourses." On the other hand, Weinstein found using both quantitative and qualitative data that adolescents' perceptions of the relationship between social media use and well-being probably is more nuanced, and mostly positive. Another clear gap in the research literature is the lack of focus on potentially positive aspects of social media use. It is obvious that there are some positive sides of the use of social media, and these also need to be investigated further (Weinstein, 2018;Birkjaer and Kaats, 2019). Genderspecific analyses are also lacking in the research literature, and there is reason to believe that social media use have different characteristics between the genders with different relationships to mental health. In fact, recent findings indicate that not only gender should be considered an important factor when investigating the role of social media in adolescents' lives, but individual characteristics in general Orben, 2020). Analyses of socioeconomic status and geographic location are also lacking and it is likely that these factors might play a role the potential association between social media use and mental health. And finally, several studies point to the fact that social media potentially could be a fruitful arena for promoting mental well-being among youth, and developing mental health literacy to better equip our adolescents for the challenges that will surely arise Teesson et al., 2020).

CONCLUSION
Research into the association between social media use and mental health and well-being among adolescents is rapidly emerging. The field is characterized by a focus on the association between social media use and negative aspects of mental health and well-being, and where studies focusing on the potentially positive aspects of social media use are lacking. Presently, the majority of studies in the field are quantitatively oriented, with most utilizing a cross-sectional design. An increase in qualitatively oriented studies would add to the field of research by increasing the understanding of adolescents' social-media life and their own experiences of its association with mental health and well-being. More studies using a longitudinal design would contribute to examining the effects of social media over extended periods of time and help us learn about possible cause-and-effect relationships. Few studies look into individual factors, which may be important for our understanding of the association. Social media use and mental health and well-being are complex phenomena, and future studies could benefit from specifying the type of social media use they focus on when trying to understand its link to mental health. In conclusion, studies including more specific aspects of social media, individual differences and potential intermediate variables, and more studies using a longitudinal design are needed as the research field matures.

AUTHOR CONTRIBUTIONS
JS conceptualized the review approach and provided general guidance to the research team. VS and JS drafted the first version of this manuscript. JS, GH, and LA developed the draft further based on feedback from the author group. All authors reviewed and approved the final version of the manuscript and have made substantive intellectual contributions to the development of this manuscript.

FUNDING
This review was partly funded by Regional Research Funds in Norway, funding #RFF297031. No other specific funding was received for the present project. The present project is associated with a larger innovation-project lead by Bergen municipality in Western Norway related to the use of social media and mental health and well-being. The innovation-project is funded by a program initiated by the Norwegian Directorate of Health, and in Vestland county coordinated by the County Council (County Authority). The project aims to explore social media as platform for health-promotion among adolescents.

ACKNOWLEDGMENTS
We would like to thank Bergen municipality, Hordaland County Council and Western Norway University of Applied Sciences for their collaboration and help with the review. We would also like to thank Senior Librarian Marita Heinz at the Norwegian Institute for Public Health for vital help conducting the literature search.