The Relationships between Smartphone Addiction of 2 Middle School Students and Smartphone Usage 3 Types , Depression , ADHD , Stress , Interpersonal 4 Problems , and Parenting Attitude . 5 6

The purpose of this study was to examine the relationships between smartphone addiction 15 of middle school students and smartphone usage types, depression, attention deficit hyperactivity 16 disorder (ADHD), stress, interpersonal problems, and parenting attitude. This study was also 17 performed with the aim of verifying the relationships among depression, ADHD, perceived stress, 18 interpersonal problems, and parenting attitude, which are predictors of smartphone addiction. The 19 subjects of this study were 487 local middle school students (234 males and 253 females). The 20 measurement instruments used were the smartphone addiction scale, depression scale (PHQ-9), 21 ADHD scale (K-ARS), perceived stress scale (PSS), interpersonal problem scale (KIIP-SC), and the 22 parenting attitude scale. This study identified the relationships between the variables with 23 correlation analysis and examined the predictors of smartphone addiction with hierarchical 24 multiple regression analysis. According to the study results, the factors that influenced smartphone 25 addiction were gender, stress, and interpersonal problems. In addition, when the confounding 26 variables of smartphone addiction were controlled to examine the effects of smartphone usage types 27 on smartphone addiction, social media use and music/videos were found to have a positively 28 significant effect on smartphone addiction while study had a negatively significant effect. The order 29 of the usage types with the highest influence on smartphone addiction was enjoying music/videos, 30 social media use, and study. This suggests that selective intervention depending on the main 31 smartphone usage type can be effective. 32

parenting attitude scale. This study identified the relationships between the variables with 23 correlation analysis and examined the predictors of smartphone addiction with hierarchical 24 multiple regression analysis. According to the study results, the factors that influenced smartphone 25 addiction were gender, stress, and interpersonal problems. In addition, when the confounding 26 variables of smartphone addiction were controlled to examine the effects of smartphone usage types 27 on smartphone addiction, social media use and music/videos were found to have a positively 28 significant effect on smartphone addiction while study had a negatively significant effect. The order 29 of the usage types with the highest influence on smartphone addiction was enjoying music/videos, 30 social media use, and study. This suggests that selective intervention depending on the main

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Smartphones are indispensable tools for people of all ages around the world today, and it has 37 become difficult to imagine everyday life without a smartphone. The use of smartphones has 38 brought drastic changes to our lives, habits, social activities, values, and family relationships and 39 social interactions [1,2]. Especially for the youth who are sensitive to new technology and media 40 use, smartphones have become an important part of their lives [3]. According to a recent study, the 41 domestic middle and high school students' smartphone ownership rate exceeded 95%, which is 52 and connectivity of smartphones allow users to easily access information anytime and anywhere.

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Therefore, adolescent users who are vulnerable to behavioral addiction, are more likely to develop 54 an addiction to smartphones [9,4]. Smartphone addiction is defined as a state where the excessive 55 use of a smartphone, the withdrawal symptoms of feeling anxious and nervous when without the 56 smartphone, and higher tolerance that causes increased use to obtain the same level of satisfaction

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Previous studies reported that excessive smartphone use by adolescents was associated with 62 their gender, health problems, psychopathological state (depression, anxiety, high stress, low mood, 63 etc.), and behavioral problems [8,9,14,15,16,17]. This is because adolescents are easily affected 64 by external stimuli, interpersonal problems, and emotional changes [3]. In addition, excessive 65 smartphone use by adolescents can affect conflict with their parents, low academic achievement, 66 and low satisfaction with life, leading to failure in performing developmental tasks and difficulties 67 in adaptation [18,19]. The focus of previous studies related to smartphone addiction has been on 68 the characteristics of people who use smartphones excessively. These studies have been conducted 69 to investigate smartphone users' addictive use of these devices, its side effects, and factors 70 influencing smartphone addiction [20,21,22,23]

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Smartphone usage types are categorized into playing games, social media use, news reading, 74 entertainment (music/videos), exchanging text messages, making and receiving calls, commercial 75 transaction, and location-based service [17,25,27,28,29]. In fact, most of the preceding studies

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This study also intended to verify whether the smartphone usage types could serve as the 84 predictors of smartphone addiction even when the major variables found to predict smartphone 85 addiction in previous studies conducted on adolescents were controlled.

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Depression is closely related to media addiction [37]. Kim et al. (2015) reported that depression is 98 the most important factor influencing smartphone addiction, and the higher an individual's 99 tendency to be depressed, the more he uses the smartphone as a way to resolve internalized 100 conflicts.

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In the case of ADHD, a domestic study reported smartphone addiction in 40.0% of ADHD 102 patients, and children with ADHD were found to use smartphones more often as a compensatory 103 behavior for their low self-esteem, which means that they are exposed to the higher risk of being

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The parenting attitude of parents [38,39,40] was selected among the family environment 106 factors. Among the various variables that affect adolescents' smartphone addiction, those related to 107 family issues were found to have the greatest influence [41]. This is because the parenting attitude 108 of parents has a great influence on adolescents whose independence as adults is delayed [42].

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Another reason is that parents' understanding and cooperation are essential in solving the problem

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With regard to stress, it was found that smartphones were considered and preferred as a 116 cyberspace that allows adolescents to relieve their stress, providing anonymity, and easy entry and

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While the existing study divided smartphone usage types into 1) study, 2) entertainment (music/videos), interaction as in the existing study [17]. The instruction "Some items regarding the purposes of app (e.g.

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Facebook) use may be confusing as the stated purposes can also be considered its functions, but choose 166 an answer that best reflects your main purpose for app use" was added to the questionnaire, so that the 167 study subjects can distinguish their social media use types. Therefore, this scale was finally constructed

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The research also found a negative correlation (r=-.11-.21, p<0.5) between smartphone addiction and 239 the two variables, study and positive parenting attitude) [ Table 2].

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Consistent with the results of previous studies on smartphone addiction and stress [17,46], this 299 study found that the higher the stress is, the greater its influence on smartphone addiction. When

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On the other hand, depression, ADHD, and parenting attitude of parents showed a significant 304 relationship with smartphone addiction. However, these correlations were not observed in regression 305 analysis. This suggests that interpersonal problems and stress can be stronger predictors of 306 smartphone addiction than depression, ADHD, and parenting attitudes.

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Among the smartphone usage types, social media use and music/videos positively predicted 308 smartphone addiction. This result is consistent with previous research findings that the use of social 309 media is a predictor of smartphone addiction [4,17,25,26,55], while showing that enjoying 310 music/videos is also a positive predictor of smartphone addiction [17,29].

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This study classified smartphone usage types into social media use and music/video. In the case 313 of YouTube and Facebook, however, these platforms have combined the function related to the 314 formation of social relationships, which is intrinsic to social media and other various functions related 315 to music/videos. Since the two factors that influence smartphone addiction are combined in a 316 complex manner in the two platforms, further exploration of their influence is needed.

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The smartphone usage type study was found to have a negative effect on smartphone addiction.

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Higher graders of elementary school are in the stage of "industry vs. inferiority" according to

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Erikson's psychological development theory, and experiencing a sense of accomplishment by making 335 efforts has an important influence on them. As many of the smartphone games are designed for single 336 players rather than for group players, it seems that smartphone games stimulate a sense of 337 accomplishment in higher graders of elementary school, engrossing them in these games.

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On the other hand, as middle school students are in a stage of "identity vs. role confusion" that 339 characterizes adolescence, peer relationships are very important to them. Therefore, they seek to be 340 part of a community where they can share culture and play together with their peers rather than 341 engaging in smartphone games that are relatively more focused on single play. Therefore, it is 342 considered that computer games in PC cafes where they can interact with their peer community are 343 more preferred by adolescents to smartphone games. This suggests that research on which platform 344 each age group mainly plays games in relation to their developmental age is also necessary.

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The limitations of this study are as follows. First, the subjects of this study were confined to 346 middle school students in an area of ChungBuk Province. There can be differences in students' experiences from those of middle school students. Therefore, it will be necessary to consider the 353 regional differences among study subjects and to extend the age range of the subjects in future studies.

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Third, since the measurement was carried out with the study subjects' responses based on their 363 personal perception by using a self-report questionnaire, the respondents' subjective interpretations 364 may be included in the survey results. Therefore, there are limits in generalizing the results of this 365 study, and follow-up studies that investigate the perspectives of parents and teachers are needed.

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Despite these limitations, this study is significant in that it provides basic data for the study on 367 smartphone addiction and usage types, where few studies have been carried out on these topics.

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Particularly with the rapid spread of smartphones, while studies on smartphone use and addiction 369 have been actively conducted, there have been relatively fewer studies on content related to the 370 unique functions of smartphones, that is, smartphone applications that correspond to usage types.

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This study focused on the types of smartphone usage and examined the relationship between these 372 types and smartphone addiction, to verify that there are significant differences in the levels of