# Creative beyond TikToks: Investigating Adolescents’ Social Privacy
Management on TikTok

Nico Ebert<EMAIL_ADDRESS>0000-0002-9683-4792 Zurich University of
Applied Sciences, School of Management and LawTheaterstrasse
17WinterthurZurichSwitzerland8401 ,  Tim Geppert  Zurich University of Applied
Sciences, School of Management and LawTheaterstrasse
17WinterthurZurichSwitzerland8401 ,  Joanna Strycharz  University of
Amsterdam, Faculty of Social and Behavioural SciencesNieuwe Achtergracht
166AmsterdamNorth HollandNetherlands8401 ,  Melanie Knieps  University of
Zurich, Digital Society InitiativeRämistrasse 69ZurichZurichSwitzerland8401 ,
Michael Hönig  Zurich University of Applied Sciences, School of Management and
LawTheaterstrasse 17WinterthurZurichSwitzerland8401 and  Elke Brucker-Kley
Zurich University of Applied Sciences, School of Management and
LawTheaterstrasse 17WinterthurZurichSwitzerland8401

###### Abstract.

TikTok has been criticized for its low privacy standards, but little is known
about how its adolescent users protect their privacy. Based on interviews with
54 adolescents in Switzerland, this study provides a comprehensive
understanding of young TikTok users’ privacy management practices related to
the creation of videos. The data were explored using the COM-B model, an
established behavioral analysis framework adapted for sociotechnical privacy
research. Our overall findings are in line with previous research on other
social networks: adolescents are aware of privacy related to their online
social connections (social privacy) and perform conscious privacy management.
However, we also identified new patterns related to the central role of
algorithmic recommendations potentially relevant for other social networks.
Adolescents are aware that TikTok’s special algorithm, combined with the app’s
high prevalence among their peers, could easily put them in the spotlight.
Some adolescents also reduce TikTok, which was originally conceived as a
social network, to its extensive audio-visual capabilities and share TikToks
via more private channels (e.g., Snapchat) to manage audiences and avoid
identification by peers. Young users also find other creative ways to protect
their privacy such as identifying stalkers or maintaining multiple user
accounts with different privacy settings to establish granular audience
management. Based on our findings, we propose various concrete measures to
develop interventions that protect the privacy of adolescents on TikTok.

TikTok, adolescent, video, privacy management, social privacy, COM-B, Behavior
Change Wheel

††journalyear: 2023††journalvolume: 2023††journalnumber: 2††doi:
XXXXXXX.XXXXXXX

##  1\. Introduction

The global popularity and rapid growth of TikTok are accompanied by problems
that are the subject of public debate. The platform has been criticized for
several privacy issues such collecting personal data from minors under the age
of 13 (FTC, 2019; European Data Protection Board, 2021) or transferring U.S.
minor’s data to China (Ryan et al., 2020). These issues are especially
alarming as a large number of platform users are underage (Statista, 2021). As
a result, the private space of children such as the bedrooms from which they
create their videos becomes visible to the world (Kennedy, 2020). TikTok has
reacted to public criticism by introducing several features to better protect
the privacy of adolescents (Terri Peters, 2021).

Implicit to the current debate is the apparent consensus that adolescents lack
the awareness or skill set to consider the possible privacy implications of
their platform use. In fact, however, little evidence is publicly available on
how TikTok is used by adolescents (Montag et al., 2021) and how they manage
their privacy on the platform (Kang et al., 2021). As short videos are the
platform’s key purpose, this immediately raises the question of how younger
users protect their privacy when they create videos. In this paper, we aim to
answer the following research question: ”How and why do adolescents manage
their privacy when creating videos on TikTok?” We build on the COM-B model for
behavioral analysis, an established conceptual framework for behavior change
widely applied in health communication and beyond (Michie et al., 2011). This
model allows us to explore not only privacy behavior, but also related users’
motivations, skills and desires. To explore adolescents’ privacy management in
video creation from the perspective of their capabilities, motivations, and
opportunities, we conducted interviews with 54 adolescent TikTok users in
Switzerland, where TikTok has gained popularity among young people (Bernath et
al., 2020).

This study contributes to the growing body of research that addresses how
adolescents manage their privacy on social networks. This topic, which is
often viewed (and judged) through the moral lens of adults, is usually met
with a sense of alarm. Empirical evidence that could serve as a better fact
base about adolescents’ online privacy behavior is largely based on platforms
that cater to a more general population (e.g., Facebook, Twitter). However,
TikTok is not only explicitly geared towards a younger audience (Lee, 2018),
but also strongly encourages the sharing of short personal videos. Although
adding text is possible on TikTok, it takes a back seat in favor of video
content. Given the particularly sensitive nature of one’s image and its link
to an individual’s personal development (European Court of Human Rights,
2022), TikTok strikes us as a particularly relevant but under-researched new
use case with the potential to enrich the ongoing debate about how – if at all
– teenagers perceive and manage their privacy (Kang et al., 2021).

This study is the first to examine how adolescents between the ages of 12 and
18 manage their privacy on TikTok when it comes to personal videos. Our
findings are based on original data from personal interviews and offer unique
insights into how privacy concerns influence young people’s online behavior.
The qualitative nature of our study helped us to understand the components
that shape sharing behavior on TikTok. Ultimately, this allowed us to make
concrete suggestions on how to effectively promote privacy-protective behavior
among adolescents on TikTok (e.g., specific training, improved app features,
and policy enforcement).

##  2\. Related Work

###  2.1. TikTok and Privacy Issues

As with many social media platforms, TikTok has come under scrutiny for its
handling of personal data. TikTok is a video-focused social network originally
started as U.S.-based musical.ly but later bought by Beijing ByteDance
Technology Ltd. The TikTok app (available for Android and iOS) allows users to
create short videos (which may only be a few seconds long) and live streams
(Kaye et al., 2021). Like YouTube, TikTok is a manifestation of user-generated
media where content is not primarily created by a limited number of producers
but by a myriad of users (Khan, 2017). Compared to other social networks such
as Facebook or Instagram, users on TikTok do not need to communicate with each
other to find a community. They can simply visit the “For You” default page to
find like-minded users (De Leyn et al., 2021; Kaye et al., 2021; Kennedy,
2020; Zulli and Zulli, 2020). Via the primary button at the center of the home
screen, users can easily record and edit short videos, apply various effects
and sounds, and reuse content produced by other users. Videos can be saved as
drafts or published immediately to be viewed by different audiences (myself,
followers, everybody) (Ltd., 2022). As of September 2021, 1 billion monthly
active users were reported (Wang, 2021), and 740 million first-time installs
were estimated in 2021 (Statista, 2021). Cloudflare, a provider of content
delivery networks, ranked TikTok as the most popular website of 2021, before
Google (Rosenblatt, 2022). TikTok is currently also gaining in popularity
among users below the official age limit of 13 years (Demeulenaere et al.,
2020). In Switzerland, three-quarters of all adolescents had a TikTok account
in 2020 (behind Instagram and Snapchat with both over 90%) (Bernath et al.,
2020). Younger adolescents (12-15 years) were even more likely to have a
TikTok account than older adolescents (16-19 years). Slightly more girls (78%)
used it than boys (68%). 51% of all adolescents stated to use it at least
multiple times per week, and 38% daily (Bernath et al., 2020). However, little
is known about how young users think about the data they share on the
platform.

The app has raised numerous severe security and privacy concerns (e.g., (Wong,
2019; Eberl, 2019; Bergman et al., 2020; Dodds, 2020; Krause, 2022)) and
caught the attention of the international authorities in the U.S. and EU
(European Data Protection Board, 2021; Roumeliotis et al., 2019; Ryan et al.,
2020). For example, an analysis of the app revealed extensive aggressive user
tracking (e.g., including techniques such as fingerprinting) and data sharing
with other websites (e.g., sharing searches with Facebook) (Eberl, 2019). The
app could also potentially collect other personal data from the user’s
smartphone (e.g., data from the clipboard (Dodds, 2020)). Since young people
have always been an important user group of TikTok, concerns have been raised
about ByteDance’s handling of their personal data. For example, in February
2019 ByteDance was fined USD 5.7 million by the U.S. Federal Trade Commission
(FTC) because musical.ly had collected information from minors under the age
of 13 in violation of the Children’s Online Privacy Protection Act (FTC,
2019). Due to the death of a 10-year-old TikTok user, the Italian data
protection authority has banned TikTok from processing the data of users whose
age could not be determined with full certainty (European Data Protection
Board, 2021). Also, the transfer of minors’ data to China after the
acquisition of U.S.-based musical.ly had caused a serious backlash in the US
and EU (Roumeliotis et al., 2019; Ryan et al., 2020). As recent as June 2022,
evidence surfaced that ByteDance has repeatedly accessed U.S. user data from
China – a practice that they had denied three years earlier when similar
criticism was raised (Emily Baker-White, 2022).

TikTok has reacted to public criticism with several privacy-related updates to
the original app. As part of its settlement with the FTC, the platform
introduced an age-verification process for its users based on self-
declaration, meaning users can provide a false age (Lee, 2019). Further
changes included extended parental control features (Kastrenakes, 2020) and
privacy settings contingent on the app users’ age statement (Terri Peters,
2021). While children below 13 cannot use the app, adolescents between the
ages of 13 and 15 are automatically switched to a “private account” as a
default option, limiting those who can view their videos to approved
followers. When 16- and 17-year-old users imitate an existing video in the
form of a “duet” (split-screen video) or “stitch” (video incorporating a short
clip of someone else’s content), these are automatically restricted to
“friends only”. Only users who are 18 and older can buy and send virtual
gifts. However, it is unclear if and how TikTok’s efforts have affected users’
privacy management.

###  2.2. Adolescents’ Privacy Management on Social Media

From the moment adolescents started to use online social networking sites,
“online privacy” has been a major topic of discussion (Feng and Xie, 2014).
Informational privacy can be defined as “the claim of individuals, groups or
institutions to determine for themselves when, how, and to what extent
information about them is communicated to others” (Westin, 1967). Research on
online privacy and adolescents can be divided into two categories:
“institutional privacy” and ”social privacy” (Raynes-Goldie, 2010).
Institutional privacy refers to the data collection practices by organizations
(e.g., for commercial purposes) (Raynes-Goldie, 2010; Young and Quan-Haase,
2013). The focus of this paper is social privacy, i.e., issues related to
sharing personal information with others (e.g., friends and family). According
to the theory of ”networked privacy,” individuals do not have complete control
over the sharing of their personal information within social connections
(e.g., on social media) because privacy is not managed by individuals alone,
but by networks of individuals collectively (Marwick and boyd, 2014).

Young people are often seen as particularly vulnerable social media users with
limited capacities to protect their privacy (De Leyn et al., 2019; Marwick and
boyd, 2014). At the same time, they are also portrayed as individuals who put
themselves and others at risk with their naive and reckless social media
behavior (De Wolf and Joye, 2019). Following this logic, numerous guides for
parents emphasize the importance of modifying privacy settings and monitoring
their children’s behavior (e.g., (Hodge, 2020)). However, there has also been
a pushback to this alarmist perspective by scholars who suggest that
adolescents’ online privacy should be addressed based on empirical research
rather than paternal instinct (Wisniewski et al., 2022).

Empirical evidence from social networks other than TikTok (e.g., Facebook)
suggests that adolescents are aware of their social privacy and actively
manage their privacy on social media. As described by boyd (boyd, 2014),
adolescents want to avoid surveillance from parents, teachers, friends and
other meaningful persons in their lives (that is what “online privacy” means
to them). Adolescents’ social media use seems to generally prompt increased
disclosure of personal information (Shin and Kang, 2016). However, frequent
sharing of content does not imply that adolescents share indiscriminately, nor
that the content is intended for a wider audience (Marwick and boyd, 2014).
Indeed, adolescents are concerned about their privacy and capable of
protecting it (Balleys and Coll, 2017; Blank et al., 2014; De Wolf, 2016;
Livingstone et al., 2019). Contrary to conventional wisdom, young people are,
in fact, more likely to protect their privacy on social media than older
people (Blank et al., 2014). Madden et. al found several strategies
adolescents use on social media to manage their identity and protect sensitive
information (Madden et al., 2013). These strategies include deleting friends,
faking names, deleting content, withholding/faking information, and changing
privacy settings (Dennen et al., 2017; Heirman et al., 2016; Mullen and Fox
Hamilton, 2016). They also employed different “zones of privacy” by using
different channels for disclosing personal information to maintain intimacy
with friends while protecting their privacy from their parents and strangers
(Livingstone, 2008). Privacy management can also mean modifying social media
content to shield it from audiences (Madden et al., 2013; Mullen and Fox
Hamilton, 2016). This practice is referred to as “social steganography” or
encoding a message for a defined audience (Marwick and boyd, 2014).
Adolescents’ privacy management is influenced by various factors such as their
social environment (e.g., friends, parents), prior (negative) experiences as
well as the saliency of privacy settings (Livingstone et al., 2019; Zarouali
et al., 2018).

Despite the existing evidence on adolescents’ social media use on other social
networks, researchers argue that existing findings might not be directly
applicable to TikTok (Montag et al., 2021). Compared to other networks such as
Facebook or Instagram, TikTok mainly thrives on content exploration and
(re)-creation (Zulli and Zulli, 2020). The focus is not on the interaction
between users and their social network but the interaction with users’ videos
proposed by an algorithm (Bhandari and Bimo, 2020). The main feature, the “For
You” page, presents an endless stream of personalized, publicly available
videos. Seeing them will motivate users to react and create similar content
(e.g., through features such as “duet” or “stitch”). TikTok might therefore
pose a particular threat to adolescents’ privacy because a space previously
conceptualized as private and safe can easily become a space of public
visibility, surveillance, and judgment (such as in the case of a teenager
being seen to perform a dance routine in their bedroom) (Kennedy, 2020).

Only a few studies have investigated adolescents’ privacy management on
TikTok. There is some evidence that privacy management on TikTok is considered
as crucial by adolescents (De Leyn et al., 2021) and becomes more stringent at
higher perceived risks (Kang et al., 2021). However, it is unclear how and why
adolescents manage their privacy on TikTok.

###  2.3. COM-B Model

As we were interested in the components that shape privacy behavior, we chose
the COM-B model, which has been used in exploratory studies (e.g., (Flannery
et al., 2018)) and a series of contexts to change behavior (e.g., (Barker et
al., 2016)), as the conceptual framework for our analysis. Many behavioral
theories have been developed, often with overlapping but differently named
constructs (Michie et al., 4 05) and limited guidance on choosing an
appropriate theory for a particular, real-world context (Michie et al., 2011).
As a consequence, theories are often under-used to understand real-world
contexts and to design real-world solutions, which makes replication,
implementation, evaluation, and improvements difficult (Eccles et al., 2012;
Michie et al., 2011). Researchers have argued that a comprehensive meta‐model
or “supra‐theory” model of behavior – like the COM-B model – is needed that is
applicable across contexts (Eccles et al., 2012; Michie et al., 2011). As a
meta-model of behavior, the COM-B model does not come with a pre-determined
set of context-specific predictions that are common for many behavioral
theories. COM-B is based on several existing social cognition models and has a
broader understanding of behavior, having ”also […] automatic processing at
its heart [like emotions and habits], broadening the understanding of
behaviour beyond the more reflective, systematic cognitive processes that have
been the focus of much behavioural research […] (for example, social cognition
models such as the Theory of Planned Behaviour)” (Michie et al., 2011). Its
comprehensive nature and flexibility made it a good fit for the exploratory
nature of our study that was not constrained by the conceptual boundaries of a
single theoretical framework. Furthermore, the model comes with hands-on
actionable advice on appropriate interventions in a given context in form of a
holistic behavior change framework (“Behavior Change Wheel”) (see (Michie et
al., 2011)).

The figure depicts the COM-B model with its four dimensions capability,
motivation, opportunity and behavior

Figure 1. The COM-B model (Michie et al., 2011). The three components
capability (C), opportunity (O) and motivation (M) must be present for a
behavior (B) to occur. They interact over time and form a dynamic system with
positive and negative feedback loops (West and Michie, 2020).

As illustrated in Figure 1, the COM-B model is based on three components –
capability (C), opportunity (O), and motivation (M) – that shape a person’s
behavior (B) (Michie et al., 2011). Firstly, capability is a subject’s
psychological ability (including necessary comprehension, knowledge, and
skills) as well as the physical ability (e.g., control of the body) to engage
in a behavior. Secondly, motivation can be defined as the subject’s mental
processes that energize and direct behavior. It includes the reflective
motivation that involves conscious processes (e.g., goals, plans, and
evaluations) as well as automatic processes (i.e., habitual, instinctive,
drive-related, and affective processes). Finally, opportunity is defined as an
attribute of the environmental system (unlike capability and motivation) that
enables or facilitates a behavior. Opportunities can be physical (e.g.,
technical features of an app, material, financial, and time) and social (e.g.,
norms and culture). In this study, we analyzed the participants’ capabilities,
opportunities, and motivation to engage in privacy behaviors.

Firstly, capability is a subject’s psychological ability (including necessary
comprehension, knowledge, and skills) as well as the physical ability (e.g.,
control of the body) to engage in a behavior. Secondly, motivation can be
defined as the subject’s mental processes that energize and direct behavior.
It includes the reflective motivation that involves conscious processes (e.g.,
goals, plans, and evaluations) as well as automatic processes (i.e., habitual,
instinctive, drive-related, and affective processes). Finally, opportunity is
defined as an attribute of the environmental system (unlike capability and
motivation) that enables or facilitates a behavior. Opportunities can be
physical (e.g., technical features of an app, material, financial, and time)
and social (e.g., norms and culture).

In our exploratory study, we did not focus on identifying interactions between
COM-B components that explain a specific target behavior. Rather, our scope
was first to learn about the full range of behaviors and explanatory factors
associated with adolescents’ privacy management.

##  3\. Methodology

###  3.1. Research Ethics

This paper is based on semi-structured, one-to-one interviews with adolescents
in the Canton of Zurich, Switzerland, conducted in November 2021. In total, we
visited two secondary schools (one in the city of Zurich and one in the
greater Zurich area) and three youth centers (all in the city of Zurich). All
interviews were audio-recorded and transcribed verbatim. Ethical approval was
obtained from our university’s institutional review board. Study participants
provided written informed consent. For subjects below the age of 16,
additional consent was sought from the parents. The interviews were voluntary
and conducted at the institutions from which the subjects had been recruited.
Digital, personalized shopping vouchers with a value of CHF 20 (~USD 19) were
offered to study participants as compensation. The amount and type of the
vouchers was determined beforehand together with the adolescents’ supervisors
(i.e., teachers, social workers) in order to not create an inappropriate but
still sufficient incentive. After the interviews, in agreement with the
participants, WhatsApp was used to deliver the individualized vouchers to the
participants and to allow them to review their personal interview transcripts.

Several steps were taken to protect the participants identity without
compromising the transparency of our research process. To begin with, all
personally identifiable information was removed (e.g., references to persons,
locations) and participants’ names were replaced with pseudonyms. Furthermore,
the study data was stored in line with our university’s storage policy and
only the involved researchers had access to the files. Finally, the original
audio files were deleted from all devices half a year after recording together
with other remaining personal data (e.g., phone numbers, WhatsApp chats,
digital vouchers).

###  3.2. Sample and Procedure

Due to the lack of research on this topic, we chose a highly exploratory
approach. To identify information-rich cases and make optimal use of available
resources, we drew a purposive sample (Etikan et al., 2016). We used social
media and search engines to find institutions in the Canton of Zurich (e.g.,
secondary schools, youth work, youth associations, museums) with contact with
adolescents between 12 and 18 years of age. Afterward, principals of
participating institutions recruited interested teachers and social workers.
They, in turn, contacted interested TikTok users in the required age group. To
extend the participant base, we applied snowballing among the interested
TikTok users. Based on our primary aim (i.e., to explore how adolescent TikTok
users manage their privacy), we chose to sample based on study participants’
age and gender (equally distributed). We decided to ignore other demographic
information such as ethnic identity. Following a pragmatic definition of
theoretical saturation (Low, 2019), no new information emerged after
approximately 40 interviews, and we ended data collection after the 54th
interview.

We chose to employ semi-structured interviews for our study because it
encourages two-way communication and provides the interviewer with the
opportunity to learn the reasons behind an answer. Some of the questions were
part of the interviewer’s guide (see Appendix), others were addressed at the
moment. The interview guide was developed based on a previous study that
applied the COM-B model in a qualitative setting (Castro et al., 2021) and
adopted to the context of the current study. After asking for demographic
information, we first explored general TikTok usage and motivation. The other
questions followed the COM-B structure and were related to privacy-related
behaviors as well as the explanatory components related to the target behavior
“video creation”. We finished the interviews with questions about commercial
privacy aspects (i.e., targeted advertising and user tracking). After the
interview process was completed, study participants received a copy of their
interview transcript via WhatsApp and were invited to add information or make
amendments. Minimal revisions were made by one participant.

To analyze the content of the interviews, we used a two-step procedure that
first divided each statement into one of the four COM-B components (behavior,
capability, opportunity, motivation) before further subdividing them into
privacy-specific content. For phase one, we used a directed content analysis
approach (Hsieh and Shannon, 2005) to analyze the statements. To counter the
subjectivity inherent to qualitative data analysis, three researchers read and
coded all statements into the four COM-B domains (behavior, capability,
opportunity, motivation). On the grounds of economy in both cost and effort,
we decided against using ”intercoder reliability” (ICR). As full replication
of results was deemed unnecessary due to the exploratory and qualitative
nature of data collection and analysis, we instead followed guidelines
suggesting the use of ”multiple coding” which allows independent researchers
to cross check their coding strategies and interpretation of data (Barbour,
2001). The authors engaged in researcher triangulation (Denzin, 2017) by
discussing the emerging codes during the open coding process of the first
three interviews and developed coding guidelines. Disagreements were discussed
and resolved. Using the MAXQDA 2020 software, all responses were coded
consistent with six COM-B labels111We did not need to code “physical
capability” as the participants did not have physical impairments. (behavior,
psychological capability, automatic/reflective motivation, social/physical
opportunity). To ensure continued adherence to the agreed coding guidelines,
the three researchers regularly communicated to ensure coding consistency.

In phase two, all statements – previously labeled as one of the COM-B
components – were further analyzed for their privacy-specific content.
Therefore, an inductive thematic analysis (Braun and Clarke, 2006) to identify
themes within similarly coded statements was conducted (see Appendix for
coding scheme). One researcher identified themes across identically coded
statements and discussed them with the other researchers. A theme reflects a
collection of similar responses from at least two different study
participants. For example, responses that were coded under the COM-B label
“reflective motivation” such as “I would be afraid of stupid remarks.”, “I
have no desire to be bullied.”, and “I can do without being ridiculed in my
class’s WhatsApp group.” were allocated to the privacy-specific theme
“negative reaction avoidance”. This step resulted in a list of themes within
each of the six COM-B labels. Ultimately, the researchers reviewed and
discussed the emerging themes, merged similar themes, and re-labeled others.
By playing the “devil’s advocate” – a common way to scrutinize identified
themes (Barbour, 2001) – we sought to exploit the full potential of multiple
coding to furnish alternative interpretations of our findings. The anonymized,
coded interview transcripts are publicly available at osf.io/z8d3w.

##  4\. Results

A total of 54 adolescents aged between 12-18 years (15 ± 1.82 years) were
interviewed, of which half (27) were female (see Table 1). Interviews ranged
from 5 to 21 minutes in length, with a mean of 12.6 min per interview (SD =
3.91). Most users attended secondary school, and 80% had used the app for more
than one year. Half of the study participants admitted using TikTok between
one and three hours per day.

Table 1. Characteristics of one-to-one interview participants (n = 54) Variables | % (n)
---|---
Gender (% of females) | 50% (27)
Age | 15 ± 1.82
Educational level |
Primary level | 2% (1)
Lower secondary level | 54% (29)
Upper secondary level | 44% (24)
User since |
One year or less | 20% (11)
Between one and two years | 33% (18)
More than two years | 46% (25)
Current app usage |
Daily ¿= 3h | 17% (9)
Daily ¿= 1 and ¡3h | 50% (27)
Daily ¡ 1h | 28% (15)
Less than daily | 6% (3)

Building on the conceptional framework of the COM-B model, we identified 13
themes from the data analysis that described how and why adolescents protect
their privacy on TikTok (see Table 2). These are described in more detail in
the following. No weighting was associated with the themes in terms of their
overall contribution.

Table 2. Identified themes for adolescents’ video privacy management on TikTok based on the COM-B model. Frequency is calculated across 54 interviews. Theme |  Description | Frequency
---|---|---
Behavior |  |
Proactive privacy |  Publishing videos with control over the content and the audience | 30
Avoidance |  Publishing no videos on the platform | 24
Capability (Psychological) |  |
Past privacy incidents |  Previous negative experiences related to privacy on the platform (e.g., lost account, accidental publication) | 15
Privacy literacy |  Knowledge and skills related to privacy management in the app (e.g., audience understanding and configuration) | 53
Opportunity (Social) |  |
Negative feedback |  Negative behavior of others affects privacy management (e.g., observation of cyber-bullying) | 16
Linkability experience |  Observing that online personas can be linked to the personal sphere affects privacy management (e.g., my teacher is on the platform) | 39
Restrictive influence |  Restrictive behavior of others affects privacy management (e.g., restrictive parental mediation) | 34
Opportunity (Physical) |  |
Platform features |  Privacy-related features of the platform (e.g., audience settings, sharing via other social networks) | 46
Device features |  Privacy-related features of the device (e.g., screen time limits, deleting videos on the smartphone) | 17
Motivation (Automatic) |  |
Negative emotion avoidance |  Avoidance of negative emotions expected as a result of publication (e.g., shame, fear) | 15
Motivation (Reflective) |  |
Negative reaction avoidance |  Goal to avoid expected negative consequences of publication | 10
Privacy identity |  Privacy as a general value (e.g., also on other platforms) | 5
Publicity avoidance |  Goal to avoid expected publicity of publication | 29

###  4.1. Behavior

####  4.1.1. Proactive privacy

The participants in our study mentioned various ways to control the content of
their TikToks222The term “TikToks” is used synonymously with videos. and their
audience. Publishing content to audiences was described as reflective and non-
automatic (as opposed to a habitual, non-reflective publication of TikToks).
This behavior is also referred to as the “approach” privacy strategy (Marwick
and boyd, 2014). For example, regarding the content, study participants
described what they consider to be too sensitive for publication on TikTok and
would not publish (e.g., TikToks that reveal too much about them). Lima (F,
14) creates public videos and has 50 different accounts. She has clear privacy
boundaries regarding the video content: “I would not post TikToks where you
can see a lot of myself. I wouldn’t post videos in which I’m drunk.”. Another
form of restriction is to define who can see which type of content on the
platform. This includes TikTok users making drafts only visible to themselves
or blocking selected users from watching videos. Bärbel (F, 13) actively tries
to keep her parents from seeing her videos: “To prevent my parents from seeing
my videos, I can simply block them.”.

We identified two subthemes within the proactive privacy theme: private
creators (19 persons, 35% of the sample) and public creators (11 persons,
20%). Private creators create videos only for themselves or close friends but
do not publish them for a broad audience. A few users described the practice
of posting videos that are just visible to themselves, only to be able to then
repost them on “more private” social media such as Snapchat or WhatsApp for a
selected group of people: “I don’t post my videos. I download them, save them
under photos, then send them on WhatsApp, for example. I only use TikTok for
editing.” (Amy, F, 17).

Public creators regularly create videos for their followers or the general
public. An extreme case is Joy (F, 13), who has used TikTok since she was nine
years old (when the app was still musical.ly). She maintains 50 thematic user
accounts with different age settings and distinct followings (e.g., some
accounts for gaming-related videos and others for YouTube reposts). In
addition to managing multiple accounts, public creator Lima (F, 14) also uses
the live feature. It is available to users with at least 1,000 followers and
allows them to create personal live streams and interact with users in real
time. Lima had to set her age to 16 years to enable the live feature.

####  4.1.2. Avoidance

Some study participants reported that they do not publish videos on TikTok at
all to protect their privacy. In the literature, this is referred to as the
avoidance privacy strategy (Marwick and boyd, 2014). Peter (M, 14), one of 24
study participants (44%) we classified as a pure consumer, stated: “I’ve never
created a TikTok. I don’t even know how to do it.”. Tim (M, 12) published once
but decided to only watch TikToks afterward: “To try it out, I uploaded
something once, but nothing from me. I thought that was funny. But I prefer to
watch videos.”

###  4.2. Capability (Psychological)

####  4.2.1. Past privacy incidents

This theme refers to a specific form of privacy-related knowledge (cp. (Michie
et al., 4 05)) gained after experiencing potential or actual privacy
incidents. Potential privacy incidents are perceived as minor threats but may
lead to increased privacy awareness. “I posted my very first video by
accident. It was only seen by three people,” reported Yasmina (F, 15). Lima
(F, 14), a public creator, remembered: “I was half asleep and accidentally
posted a TikTok. The next morning, I saw that someone had commented on the
video. But I thought it was funny and not bad at all.” When TikTok updated its
app and increased the size of the “publish” button to lower the threshold for
publication, Lima decided to block app updates.

Users have also realized that some of TikTok’s privacy features can be easily
bypassed. Their awareness of the platform’s weaknesses has contributed to a
greater privacy awareness. An example is a feature that allows blocking
certain users from viewing videos, which can be easily bypassed: “If I block
people but they still want to see my TikToks, they immediately make an extra
fake account and continue seeing them.” Roswitha (F, 15). However, she found a
way to manage her privacy: “Since these users have too few followers, I simply
block them again or ignore them depending on the video.”.

A more serious subtheme are actual privacy incidents. Bärbel (F, 13) had to
realize that she was not anonymizing herself sufficiently: “I wore a mask on
my face in the video, anonymously, so to speak. But the people who deal with
me every day recognized me by my outfit, my room, and my hairstyle and posted
the video in the class WhatsApp chat.”. Anna (F, 14) reported losing her
account and not being able to reclaim it through TikTok’s customer support. At
the same time, other users were still able to watch her videos: “I made videos
of myself when I was 9 and then lost the account. Now the videos are still
public, but I can no longer access them.”.

####  4.2.2. Privacy literacy

Privacy literacy can be defined as a combination of factual or declarative
(’knowing that’) and procedural (’knowing how’) knowledge about online privacy
(Trepte et al., 2015). Concerning the publication of videos on the platform,
adolescents need to have the knowledge and skills to assess and manage
audiences and content as needed.

Respondents mentioned, for example, that the algorithm might present a video
on TikTok’s center stage: “It depends on how popular a video is and only then
does it appear on the For You Page.” (Bärbel (F, 13)) or that public videos
can also be watched without having a TikTok account: “From Google or Safari
you can type in TikTok and view the videos.” (Aron (M, 13)). They also
described how to find out which of their peers used TikTok: “When you post a
video, it spreads immediately and then you know who has TikTok and who does
not. Because so many people have TikTok now, it has become weird for me to
post TikToks.” (Elsa (F, 14)). Respondents also described their audience and
content management skills. The private creator Bea (F,14) only publishes for a
strictly curated list of followers and therefore has established an approval
process that allows her to maintain the desired level of privacy: “I get to
know new classmates first and only then give them my TikTok account.
Afterward, they tell me they sent a request and I accept them as followers in
the app.” (Bea (F, 14)). Furthermore, the adolescents interviewed were also
able to assess different levels of sensitivity of content in terms of their
privacy and select an adequate audience accordingly: “My buddy and I made 10
TikToks in which we share our weekend activities with people. Some have 60,000
views. But we think carefully what to make public.” (Alex (M, 18)).

The adolescents also talked about various app settings needed to manage the
audience, such as the activation of the private account “Switching to the
private account takes only two minutes. This is not difficult.” (Alexandra (F,
12)) or knowing the publication status of a video: “A draft is rendered
greyish and blurry. When published, it is bright and jumps right out at you.”
(Alexander (M, 15)). Some adolescents also perform “digital housekeeping”
activities by removing content related to a specific event or as a habit: “As
I became older, I started to delete old videos.” (Ariane (F, 15)).

###  4.3. Opportunity (Social)

####  4.3.1. Negative feedback

Negative feedback refers to expected or observed negative feedback from others
(such as harsh comments to videos). Study participants reported negative
reactions on the platform (e.g., from strangers or people from the same
school) as an explanation for their privacy protection behavior. Alexander (M,
15) mentioned a general culture of mutual criticism: “Many of the famous
TikTokers sometimes make mistakes. Afterwards, everyone makes fun of them in
videos.”. Other respondents mentioned negative reactions from their peers that
had influenced their behavior: “A friend went viral with a video. Then she got
yelled at on the street. It would annoy me.” (Katja (F, 17)).

####  4.3.2. Linkability experience

Similar to the perception of negative feedback, the realization of how easily
online personas can be linked to the personal sphere can also lead to more
restrictive publication behavior. Study participants perceived the platform as
a public space shared by acquaintances and strangers. However, by recognizing
people from their school on their “For You” page, study participants realized
that they, too, could be easily recognized. As Georg (M, 15) put it: “There
are maybe ten or twenty people in the school building who do [public] TikToks
regularly. You suddenly realize: I know that guy from TikTok. That’s the
reason why I don’t publish.”. In addition to peers, respondents also described
experiences that made them understand that acquainted adults in authority
positions would be able to see their TikTok as well. Sibylle (F, 15) realized
this: “My music teacher was on TikTok singing a song.”. Therefore, Sibylle
also does not publish so as not to be recognized by everyone on the platform.

####  4.3.3. Restrictive influence

Restrictive influence refers to others (e.g., close friends or parents)
perceived to be restrictive or restricting study participants’ video creation
behavior. Some interviewees reported that their friends did not publish on
TikTok, which in part motivated why they did not publish, either. In
mentioning his peers, Felix (M, 12) stated: “Most of the people I know don’t
upload anything of themselves where they show their face.”. Another example is
restrictive mediation by parents or relatives: “My eight-year-old cousin
accidentally posted a video with my smartphone. His uncle saw it on his For
You page, so I deleted it.” (Sibylle (F, 15)).

###  4.4. Opportunity (Physical)

####  4.4.1. Platform features

Age verification is a key platform feature intended to protect the privacy of
young users (not limited to creating videos) and the subject of much public
discussion. In the semi-structured interviews, 29 of the interviewed
participants were also asked what age they provided. Two-thirds admitted that
they had given a false age when they registered (indicating, e.g., the age of
their parents). The main motivation for this behavior was to be able to use
TikTok in general (for those below the age of 13) or all its features. Some
study participants, like Martin (M, 14), also had misconceptions about
possible age restrictions: “Because otherwise, TikTok won’t let me watch
videos.”.

However, study participants also described how they used TikTok’s features for
privacy purposes in general. This includes using a nickname instead of their
real name, limiting the use of personal information on their profile page, and
not linking their TikTok account with other social media accounts (e.g.,
Instagram). While some interviewees do not use a name at all: “Why should
people know my name? I have replaced my name and individual letters with an
X.” (Ali (M, 12)), others actively involve their parents to make use of the
in-app parental controls that restrict their app access.

Study participants also reported using various features related to audience
configuration, such as creating personal drafts, activating a private account,
deleting videos, or blocking users. Public creators sometimes create multiple
“privacy-tailored” user accounts with specific follower groups for content of
special sensitivity. Where the features offered by the platform are perceived
as too limited or ineffective, the adolescents used creative workarounds not
originally anticipated by the platform provider. For example, it is not easily
possible to download and share drafts of videos that are not yet published.
Amy (F, 17), however, described a popular workaround: “I post videos on
TikTok, but only for me. Afterward, I’m able to download them to share them
with my friends on WhatsApp.”

####  4.4.2. Device features

As part of the greater sociotechnical system, some devices (e.g., smartphones)
offer features that affect user privacy. For example, study participants make
use of the “digital wellbeing” functionality of their smartphone to limit
their screentime: “I used TikTok three hours a day because I didn’t know
anything better to do with myself. Now I’m trying to get a handle on this with
a screen time limit.” stated Matthias (M, 17). Sandra (F, 14) was one of the
study participants who used smartphone features to share videos more
selectively: ”You can take a screenshot of drafts with an iPhone and then send
them via WhatsApp or Snapchat.”. As mentioned earlier, Lima (F, 14) noticed
that the size of the red “publish” button grew with each new app update
compared to the grey “save as draft” button. Fearing accidental publication,
she bypassed this potentially manipulative design pattern (“dark pattern”) by
using an old version of the app, which her operating system allowed her to do:
“Therefore, I have blocked the updates for TikTok on my cell phone.”.

###  4.5. Motivation (Automatic)

####  4.5.1. Negative emotion avoidance

The interviewees describe various negative emotions if they appeared in a
video on TikTok. For example, they mentioned feelings of discomfort, shame,
awkwardness, and annoyance. Milo (M, 12), who does not publish any videos,
said: “I would be embarrassed to be seen in a video.” Elsa (F, 14) reported
that her desire to avoid negative emotions had evolved. While she had posted
videos on musical.ly, she didn’t publish on TikTok anymore: “Posting TikToks
has become weird for me.”.

###  4.6. Motivation (Reflective)

####  4.6.1. Negative reaction avoidance

Another reason for not publishing personal content was negative reactions by
others to their videos such as being bullied in class (e.g., in the WhatsApp
class chat). Alexander (M, 15), who does not publish any videos, commented:
“You make a mistake, people from school see it, it gets sent on, and you get
bullied.”. Avoidance can also relate to the negative long-term consequences of
sharing personal content. As they get older, adolescents who are getting ready
to join the job market realize that their activity on TikTok could harm their
career prospects. “The Internet never forgets and if I eventually look for an
apprenticeship, it may be that my future employer sees that. That’s very bad
for my reputation.” (Lima (F, 14)).

####  4.6.2. Privacy identity

With privacy identity, we refer to a coherent set of privacy-related behaviors
and personal qualities of an individual in a social setting (Michie et al., 4
05). Some teenagers consider privacy as a value in itself and part of their
identity. For example, for Yara (F, 14), the publication of videos on TikTok
is no different from any social network activity: “It’s just not my thing. I
don’t post in general either, not even on Instagram or anything.”. Lena (F,
17) explicitly stated that she considers privacy a significant personal value:
“Privacy is important to me. I keep everything private that can be kept
private.”.

####  4.6.3. Publicity avoidance

Another motivation for restricting the publication of personal videos on the
platform is closely related to the linkability experience theme: the desire to
not attract public attention. Study participants explained that publishing on
TikTok means being in the public eye: “It’s a big platform, and I don’t want
people around me to see that I make videos.” (Anna (F,14)). While in
musical.ly, the public was described as a community of people with similar
interests and ages, on TikTok, it is perceived as a heterogenous, superficial
place with different people of all ages (including strangers, peers from the
same school, teachers, extended family members, and parents). Lina (F, 17)
described how the change in the audience had an impact on her behavior: “At
musical.ly, there were also strangers, but more my age. But TikTok is now
worldwide and there are adults everywhere. I don’t have to post anything
there.”. Her comment shows that the platform is now perceived as completely
public, whereas it used to be a more private community.

##  5\. Discussion

Our general observation of adolescents’ on TikTok is in line with previous
research on other social networks (Balleys and Coll, 2017; Blank et al., 2014;
De Wolf, 2016; Livingstone et al., 2019): Contrary to public perception which
portrays the publication of TikToks by young people as automatic and
unreflective, the adolescents in our sample actively engaged in privacy
management. They demonstrated a strong awareness of the need to manage their
online identity and social privacy on the platform. However, the interview
participants were more concerned with protecting their privacy from their
immediate social environment than with institutional or commercial privacy
issues. That is, while they were generally aware that TikTok used algorithms
to tailor video content to their particular online behavior, they were more
worried about the tangible aspects of the algorithm: that a published video
could immediately appear on a classmate’s account.

Next, we will discuss the results in more detail following the structure of
the COM-B model. While many of our findings are consistent with themes found
in previous research on other social media platforms (e.g., Facebook), a few
themes and aspects are indeed unique and – best to our knowledge – have not
yet been studied by researchers on TikTok or other platforms. The qualitative
nature of our data inform the design of very concrete interventions on TikTok
(Section 5.7).

###  5.1. Behavior

In addition to previous research on other social networks (Marwick et al.,
2010), we were able to identify two very different types of proactive privacy
behavior: public and private creation. While public creators perform privacy
management to share videos directly on TikTok, private creators merely use the
platform to create and edit videos to share them on other social networks that
they see more appropriate for such content (e.g., Snapchat, WhatsApp). It
indicates that adolescents have different ”imagined audiences” (mental
conceptualization of the people with whom the user is communicating, (Litt,
2012)) on each social network and curate who sees what by switching between
networks. A unique finding of our study is that private creators essentially
reduce TikTok, which was originally conceived as a social network, to its
extensive audio-visual capabilities and share their personal content where
social connections already exist and a higher degree of perceived control and
intimacy exists (e.g., WhatsApp). It is possible that such a practice might
also be found elsewhere (e.g., Instagram, YouTube). At a time when
adolescents’ increasingly use multiple social media platforms at once, privacy
perceptions of and management between different platforms has to be addressed
more comprehensively. That is, privacy management can no longer be seen as a
single-platform-phenomenon – an observation with important research
implications. Rather than focusing on isolated social networks with their own
privacy standards, researchers should expand their analysis to include a
cross-network view of privacy management.

###  5.2. Psychological Capabilities

Similar to previous studies on other social media platforms (Livingstone and
Helsper, 2010; Balleys and Coll, 2017; Livingstone et al., 2019), we found
that adolescents possess knowledge and skills on how to manage their privacy
on TikTok (see ”privacy literacy” theme). That is, adolescents were not only
able to assess the audience of videos but also to actively manage the audience
and content of their TikToks. As previously noted (Marwick and boyd, 2014),
privacy management can be very creative. This finding also holds true for
TikTok: some of our respondents reported using various accounts for different
audiences, blocking app updates to avoid receiving less privacy-friendly
versions of the app, and making an effort to detect fake users trying to
follow them. An interesting observation that can potentially inform other
research on social privacy management in social networks is that adolescents
on TikTok do not only use the technical features provided by the social
network itself. Instead, some are also capable of using physical opportunities
provided the device (e.g., blocking app updates, screen time management). This
example illustrates how the existence of these generic physical opportunities
provided by the operating system can influence the privacy management
capability of young TikTok users to learn about additional ways to protect
their privacy.

In line with previous research we found that negative past experiences affect
future privacy management behaviors (Livingstone et al., 2019). Incidents can
even serve as a learning opportunity (Wisniewski, 8 03). In our sample,
participants experienced near or actual privacy incidents (e.g., accidentally
publishing videos, loss of account with personal videos) that led them to
adapt their privacy management (e.g., immediately deleting accidentally
published videos, paying more attention to a publication in the future). While
our data support the hypothesis that incidents serve as learning
opportunities, it must be said that certain very extreme violations of privacy
(e.g., persistent bullying or stalking) have not been reported in our study.
It is unclear how such experiences affect privacy behavior in the long run.
Nonetheless, our findings inform future research by showing that even minor
privacy incidents without severe consequences can lead to improved
capabilities.

###  5.3. Physical Opportunities

Adolescents in our sample used various features of TikTok and the operating
system to manage their privacy (themes platform features and device features).
At the same time, they were aware of TikTok’s privacy management limitations
(e.g., the ineffectiveness of blocking users). Some of the measures TikTok has
taken to protect the privacy of younger users in response to public criticism
may not be very effective. Out of 29 study participants with whom we discussed
the topic, two-thirds used a false age. Many teenagers we interviewed have
been publishing on TikTok much before the legally allowed age of 13.
Regardless of the normative standpoint, this calls into question TikTok’s
fine-grained, age-based privacy features. Despite legislative measures such as
the Children’s Online Privacy Protection Act of 1998, this problem has been
described on other social networks in the past (Livingstone et al., 2011b, a).
Sometimes also parents help their underage children to access social networks
(boyd et al., 2011). Reasons for using social networks below the specified
minimum age are diverse (e.g., wanting to stay in touch with classmates,
wanting unrestricted access to TikTok’s features) (boyd et al., 2011).
Consequently, technical measures to protect children such as non-public
accounts or content restrictions are failing (O’Neill, 2013). boyd et. al
(boyd et al., 2011) called for abandoning ineffective age-based mechanisms.
Instead, she advocates for an honest discussion about children’s use of social
media and a rethinking of the industry to better incorporate the needs of
children and parents when developing apps.

Another issue on social networking sites is account loss (Rathore et al.,
2017). This issue was also highlighted by several of our respondents who
reported that they were unable to reclaim a video they had posted after losing
an account. As a consequence, they were unable to revoke their consent from
publishing a childhood experiment that would now remain online forever. This
is particularly problematic against the background of increasingly better
algorithms for recognizing people in images and videos and the resulting
linkability risk (e.g., Clearview AI (Hill, 2020)). To exercise the ”right to
be forgotten” as embodied in the EU GDPR, for example, the ability to reclaim
accounts and delete old videos is essential. It is unclear whether account
loss among adolescents is a broader phenomenon or whether other social
networks are affected as well.

###  5.4. Social Opportunities

Our findings on TikTok support previous research demonstrating that the social
environment of teenagers shapes their privacy behaviors (Livingstone et al.,
2019). Other social network users as well as the parents are major agents of
socialization (Feng and Xie, 2014). Social norms, which emerge as a response
to observed behavior or expected attitudes of friends and parents, influence
children’s intention to share personal information (Van Gool et al., 2015). If
friends and parents disapprove of such behavior, children tend to share less.
A recent study on TikTok described, that restrictive mediation by parents can
also lead to more restrictive disclosure behavior in children (Kang et al.,
2021).

In our study, we identified similar social influences on TikTok. Observing
strangers being publicly criticized for videos (theme negative feedback)
resulted in restrictive publication behavior by the adolescents we
interviewed. In line with previous research (Van Gool et al., 2015), the
restrictive norms and behavior of relatives, parents, and friends were also
found to have the potential to affect behavior on TikTok (e.g., not publishing
or blocking parents from videos).

What makes TikTok stand out from other social networks, is its specific
content algorithm based on a granular observation of user preferences (Klug et
al., 2021). The results of our study indicate that prevalent TikTok usage
among peers in combination with the platform’s specific algorithm that
immediately displays the published content to cohorts with similar attributes
– i.e., peers – may increase the social influence of others on adolescents’
privacy behavior (“linkability experience”). Unlike posting a video under a
nickname on YouTube that may never be discovered by peers, adolescents were
aware that posting on TikTok was potentially more privacy-invasive. They
recognized that their videos could become visible to their personal
environment (e.g., in the schoolyard). This experience led to restricted
publication behavior.

###  5.5. Automatic and Reflective Motivations

Adolescents’ motivations for protecting their privacy on TikTok were based on
either wanting to avoid publicity, to avoid negative reactions/emotions, or to
actively achieve privacy (themes negative reaction avoidance, publicity
avoidance). The adolescents interviewed reported wanting to evade the public
eye and feared negative feedback (e.g., public criticism). These are themes
previously described on other social networks (Livingstone et al., 2019). To
avoid a negative emotional outcome (e.g., shame), they refrain from having a
too public profile (theme negative emotion avoidance) (see (Büchi et al.,
2022) for a similar finding).

For some adolescents, privacy was a personal matter beyond TikTok (theme
privacy identity). That is, these teenagers were intrinsically motivated to
keep their information private - a finding that stands in contrast with
previous research on other social networks. Research suggests that, on
average, adolescents have fewer privacy concerns than young adults (Barnes,
2006; Dhir et al., 2017). However, our findings indicate that these concerns
can vary greatly across adolescents, and some may place great value on their
privacy on social media. Even though the theme was mentioned by only a few
participants, it underscores that adolescents are not a homogeneous group when
it comes to motives for managing privacy on social media. For some
participants’ being private is a personal value and their goal is to achieve a
coherent privacy behavior on TikTok and beyond.

###  5.6. Methodological Consideration

For our study, the COM-B model helped to holistically understand adolescents’
privacy management on TikTok related to the creation of videos. It has a solid
theoretical foundation and – according to its authors – can be applied across
various contexts. However, much of the research to date has applied the COM-B
model to health-related behaviors such as smoking cessation and lowering
cardiovascular disease risk (Michie et al., 4 05). Our study, which showed
that the COM-B model is also a suitable analytical framework for studying
privacy behavior, provides yet another use case. By demonstrating its
relevance to the privacy management of adolescents, we strengthen the model’s
extrinsic validity.

###  5.7. Possible Approaches for Privacy Interventions

Several of the themes we identified can be used as starting points for the
development of privacy interventions. The COM-B model is part of a theory-
driven intervention development framework called behavior change wheel (BCW),
a synthesis of behavior change frameworks (Michie et al., 2011). In the logic
of the BCW, interventions are directed at desired “target behaviors” (e.g.,
enabling privacy settings). Building on the interview findings and our
observations, Figure 2 shows different parties and ideas for potential target
behaviors affecting adolescents’ video privacy management. It focuses on which
behaviors to address and does not answer the question of how to design
interventions that address these behaviors (e.g., adequate behavior change
techniques (Michie et al., 2013)).

The picture shows a middle circle (TikTok Users) surrounded by six smaller
circles (Family & Friends, Schools Youth Work, Policy Makers Privacy
Advocates, Other Platform Users, OS Vendors Other Apps, ByteDance). On each of
the circles, exemplary behaviors are noted that could be influenced by
interventions.

Figure 2. Different parties and their potential target behaviors relevant for
adolescents’ video privacy management on TikTok

Any intervention schemes to improve the privacy of adolescent TikTok users
should focus on the behavior of the adolescents themselves. The interviews
provide concrete suggestions for behaviors that adolescents already report
that improve their privacy protection. This includes encouraging young users
to remove inappropriate videos from the platform and the use of alternative
social media apps (e.g., WhatsApp) to share content (theme: proactive
privacy). Some of our participants reported regular checks if a video with the
status “published” should be set to private. They also removed their old
TikToks from the app and their smartphone. Our private creators did seldom
publish on TikTok but used alternative apps such as Snapchat or WhatsApp with
a perceived higher level of privacy and the ability to automatically delete
shared TikToks after being watched by their friends. Another possible target
behavior derived from our observations is “backing up user credentials”
(theme: privacy literacy). Some adolescents in our sample who had already
created accounts in musical.ly could not delete published videos because they
had forgotten their credentials, and were not able to prove their identity to
the TikTok support to retrieve their account. An intervention could mitigate
account loss, especially in cases where children have multiple accounts.
Finally, teenagers should be made aware of the privacy settings (e.g., the
private account) and the potential risks of not correctly setting these
(theme: reflective motivation). For example, in our interviews, participants
accidentally published a TikTok upon their first usage of the app because they
were not aware others would immediately see it.

The platform must also play an important role in safeguarding the privacy of
children and adolescents. Improving features directly related to privacy such
as improved age verification, more effective blocking of users, and
facilitating access to lost user accounts are promising approaches (theme:
platform features). As described earlier, many adolescents in our sample did
not use their real age due to various reasons. For example, they were often
unaware that the private account would have been activated by default if they
had provided their real age. As a result of providing false information, the
privacy settings were much more lenient and TikTok videos would not only be
published to followers but to everybody. Following boyd et. al’s (boyd et al.,
2011) philosophy, one possibility would be to abandon TikTok’s age-based
mechanism and incorporate the needs of children and parents when developing
the app. For TikTok, this could mean taking a certain level of responsibility
for its content and giving kids and parents ways to control what videos are
shown (e.g., via a content configuration or a separate app similar to YouTube
Kids). Even if the app adhered to the age-based privacy concept, describing
the consequences of providing real age (e.g., better privacy protection) might
encourage some youth to provide their real age. Another approach has been
lately launched by the twin app Douyin (Feng, 2021). Douyin introduced an age
verification that is not based on self-declaration only but requires – unlike
the international counterpart TikTok - user authentication and imposes
restrictions on the permitted daily use for users under 14.

Some participants also criticized that they could not effectively block users
who they wanted to prevent from seeing their videos. The problem persists
because blocked users can immediately ”respawn” under a different username.
TikTok could prevent this issue with a feature that block all accounts of the
same user (similar to Instagram (Instagram, 2022)). Some study participants
also reported feeling “nudged” by the user interface design towards publishing
TikTok video for a broad audience. Others described publishing personal
TikToks accidentally. While nudging teenagers towards better privacy behavior
is also controversial (Veretilnykova and Dogruel, 2021), presenting them with
simple alternatives (such as publishing a TikTok vs saving a local draft)
could provide a welcome middle ground. Furthermore, TikTok might also do more
to educate its users on how to protect their privacy. This suggestion is based
on our observation that capabilities varied between adolescents and TikTok
users had begun to create such privacy tutorials. The latter indicates a
demand for more support (e.g., via privacy tutorials provided by TikTok).

Family, friends, schools, and youth workers can also positively influence the
privacy management of adolescents (social opportunity themes). In addition to
supporting adolescents’ privacy efforts, their social network could use TikTok
themselves to better understand specific privacy issues. In our sample, an
uncle of an eight-year-old boy used TikTok himself and warned him about the
possibility on TikTok of publishing a video by accident. The social
environment can also advise about long-term privacy risks to the children and
adolescents of which they might not yet be aware. Among a group of adolescents
of the same class, we repeatedly heard the narrative of a classmate being
recognized on TikTok despite her wearing a mask. Due to this “risk narrative”
the whole class was aware of the potential risks of insufficient anonymization
on TikTok. A collection of such tales could be used by teachers in the
classroom to illustrate the privacy risk associated with the platform.

As users do not only interact with each other when they share videos but also
with the platform and its owner company, teenagers should also be made aware
of commercial privacy issues. Our data confirmed that adolescents’ primary
privacy focus was indeed social. To this end, adolescents would need to
understand TikTok’s business model, which heavily relies on their personal
data, and the organization behind TikTok.

Policymakers and privacy advocates are also relevant actors. Not only do they
seek to create privacy laws to protect users but also to enforce these laws
through, for example, insisting on effective age verification (theme: platform
features). Ideally, these actions are guided by evidence in collaboration with
researchers, adolescent users, and parents. For example, our findings indicate
that adolescents did not know that TikTok had taken additional measures to
protect them in 2021 (Terri Peters, 2021). While privacy legislation demands
transparency for data subjects – especially for children – this example shows
that there is room for improvement in terms of the implementation of laws.

It should also be mentioned that other TikTok users can influence an
adolescent’s privacy behavior (social opportunity themes). Older and more
experienced teenagers may have capabilities (e.g., based on their negative
experiences) that can benefit younger and less experienced users. One of our
participants reported having learned about privacy settings from a video on
TikTok. Indeed, some more experienced users have already begun to acts as
mentors. This includes the user @seansvv with 1.1 million followers, who
stated in his biography “I Read ToS [Terms of Service] So That You Don’t Have
To” and regularly posts TikTok videos related to privacy topics (SEAN
[They/Them] (2022), @seansvv).

Finally, our interviews showed that OS vendors and the vendors of other apps
contribute to teenagers’ privacy on TikTok (theme: device features). OS
vendors have implemented more and more privacy control mechanisms for their
end-users (e.g., granular rights management, location sharing notifications).
These methods all work on low-level personal data (e.g., IP address, location,
and email address). However, videos shared by adolescents on TikTok that
possibly contain more sensitive personal data with higher risks involved are
not yet covered by these mechanisms. At times when a user publishes a video
accidentally, the OS could warn them in the same way that they are warned when
sharing their location with the app. In our sample, participants reported also
manually cleaning up their TikToks in the app and on their phones. OS vendors
could provide housekeeping functionalities that would simplify removing
personal content across different social networks and on the phone.

###  5.8. Limitations and Future Research

As with most qualitative research, our sample is small and was not drawn
randomly. Therefore, we cannot claim that the results are representative of
all young people in the region under consideration, and certainly not of
Switzerland as a whole. Further validation with different samples is needed to
strengthen the findings (e.g., including subjects’ socioeconomic status).

Choosing interviews as our data collection methodology was useful to learn
more about the perspectives of adolescents in Switzerland. Nevertheless, we
are aware of the limitations associated with this method. Primarily, we relied
on self-reporting rather than behavioral observations. Self-reports can be
biased due to various influences, such as subjects’ desire to portray
themselves in a positive light. Future studies might want to gather data from
a wider range of sources, such as direct observations of privacy management
behavior (e.g., through TikTok data donations).

Based on our findings, future research could develop and systematically test
privacy interventions based on the BCW methodology. A necessary first step
would be to identify appropriate target behaviors with the greatest potential
to improve privacy management among adolescents. Our research could be a
starting point for select a “promising” target behavior reported by the
adolescents (e.g., activating the private account) to address in a target
population (e.g., pupils of a local school). To identify a baseline for each
of the potential behaviors and to select a target behavior among them, further
research would be necessary (e.g., in form of a survey among pupils).
Furthermore, additional research is required to select appropriate behavior
change techniques (e.g., increasing awareness for privacy settings) and
evaluate their effectiveness (e.g., with an experiment). Importantly, such
research could also control for factors such as socioeconomic status might
also be relevant to explain privacy-related behaviors on TikTok (Hargittai,
2010). Given that teenagers may have very heterogeneous privacy management
capabilities, motivations, and opportunities, depending on their age and
experience regarding the platform, interventions need to be tailored to the
specific target group. Large-scale intervention studies using the BCW can help
to identify effective and evidence-based policies to improve privacy
management among young people on social media platforms like TikTok.

Our interviews focused on social aspects of adolescents’ privacy management.
That is, our interviewees were more concerned with protecting their privacy
from their social environment than from the corporations dealing with their
data for commercial purposes; see (Livingstone et al., 2019). Yet, TikTok
videos are not only shared with other users but also with ByteDance. Even the
users we identified as pure consumers who only view but not create content may
have privacy issues. As the video and ad algorithms are known for their high
level of customization, they make the platform heavily reliant on personal
data including detailed user behavior (Klug et al., 2021). Both users’ active
and passive behavior on the app has consequences: The TikTok pixel allows
companies to engage in detailed web tracking of TikTok users on websites
(e.g., a user who sees the ad on TikTok might buy the product in the online
shop) (ByteDance Ltd., 2022). Further research could investigate if adolescent
users are aware of these commercial privacy aspects and how they manage them.

###### Acknowledgements.

The research reported in this article was funded by the Digital Future Fund
(DFF), which is part of the Digitalization Initiative of the Zurich Higher
Education Institutions (DIZH), Switzerland. We would like to thank all
adolescents, teachers, and social workers we contacted in conducting our
study. We also thank Frank Wieber, Katja Kurz and Manuel Günther for their
helpful comments.

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##  Appendix A Appendix

###  A.1. Interview Guide (translated from German)

  1. (1)

What’s your first name? How old are you? In what grade are you?

  2. (2)

How often do you use TikTok? How long have you been using TikTok? When did you
start to use TikTok?

  3. (3)

Do you remember how old you were when you started using the app?

  4. (4)

How many people do you follow? How many followers do you have?

  5. (5)

Do you share videos? How many? What types of videos? (Behavior)

    1. (a)

Why do you/don’t you share videos? (Motivation)

    2. (b)

If yes: How do you share videos on TikTok? (Psychological capability)

  6. (6)

Who can see your videos when they are shared? (Psychological capability)

  7. (7)

How can you influence who can see your videos? (Psychological capability)

  8. (8)

Do you restrict who can see your videos? (Behavior)

    1. (a)

If yes: Why / When do you restrict your videos? (Motivation)

    2. (b)

If no: Why? Have you ever considered restricting your videos? (Motivation)

  9. (9)

Do your friends or others restrict their/your videos? (Social Opportunity)

  10. (10)

Have you ever accidentally posted a video? If yes: What did you do?
(Psychological capability)

  11. (11)

What do you think about TikTok’s features to share/restrict videos? (Physical
opportunity)

###  A.2. Coding Scheme

Table 3 shows the hierarchical coding scheme together with the frequency of
each code calculated across the 54 interviews.

Table 3. Coding Scheme (translated from German). Frequency is calculated across 54 interviews. Code |  Description | Frequency
---|---|---
Usage_since |  Start of TikTok usage | 54
Usage_frequency |  Frequency of TikTok usage | 53
App_age |  Age entered into the app at first use | 29
Video_Behavior |  |
Avoidance |  I normally do not create/publish TikToks. | 24
Proactive |  |
PersonalCreator |  I regularly create/publish TikToks for myself and close friends. | 19
PublicCreator |  I regularly create/publish TikToks for my followers/the public. | 11
Video_PsyCapability |  |
PastPrivacyIncidents |  |
Minor |  I have perceived a potential/minor privacy incident. | 9
Severe |  I have perceived a severe privacy incident. | 8
PrivacyLiteracy |  |
AudienceContentLiteracy |  I’m aware of different audience/content types and have the ability to manage them. | 52
TechnicalLiteracy |  I have the technical knowledge and skills to manage my audience. | 50
Video_SocOpportunity |  |
NegativeFeedback |  Others show negative reactions to TikToks, that’s why I’m not active. | 16
LinkabilityExperience |  Users can be easily recognized in real life. | 39
RestrictiveInfluence |  I’m not active because others are also restrictive or enforce my privacy. | 34
Video_PhyOpportunity |  |
PlatformFeatures |  TikTok helps to ensure my privacy. | 46
DeviceFeatures |  The device helps to ensure my privacy. | 17
Video_AutMotivation |  |
NegativeEmotionAvoidance |  I don’t publish content to avoid negative emotions. | 15
Video_RefMotivation |  |
NegativeReactionAvoidance |  I don’t publish content to avoid negative reactions. | 10
PrivacyIdentity |  I don’t publish content because privacy is important to me. | 5
PublicityAvoidance |  I don’t publish content because I don’t want to be in the public eye. | 29