Abstract
Emerging research suggests that adolescents at high-achieving schools (HAS) in Western societies are at elevated risk for problem behaviours. This cross-sectional study explored whether adolescents attending HAS in a non-Western setting show similar risk patterns and if contextual (school-, family-, and peer-based) factors typically associated with the excessive pressures to achieve predict these problems. Participants were 237 adolescents (14–18 years old), and one of their parents, who were recruited from high-achieving private schools in Hong Kong. The parent-child dyads completed questionnaires on youth internalizing and externalizing problems and perceived stressors. Multiple linear regressions were conducted to test whether academic demands, parent-related stressors, and social status among peers were associated with youth problem behaviours, after controlling for age and gender. The study found that nearly half of the female adolescents and over a third of the males met borderline-clinical levels (≥ 86%ile) of internalizing problems; moreover, more females than males met clinical criteria (≥ 98%ile) for self-reported externalizing problems and parent-reported internalizing problems. Academic demands, parent-related stressors, and social status among peers predicted youth-reported internalizing problems; and the latter two factors contributed parent-reported internalizing problems. However, only parent-related stressors significantly predicted youth- and parent-reported externalizing problems. The findings provide preliminary indication that HAS adolescents from Hong Kong may be an “at risk” group, highlighting the need for increased awareness and targeted interventions.
A growing body of research suggests that adolescents who attend high-achieving schools (HAS) are at elevated risk for problem behaviours (Luthar et al., 2020a). Despite significant educational – and often financial – advantages, studies show that HAS youth tend to report higher rates of depression, anxiety, and somatic symptoms compared to national norms (Luthar & Barkin, 2012; Luthar & Becker, 2002). They also report similar or higher rates of delinquency and substance use compared to their peers from less well-resourced inner-city schools (Coley et al., 2018; Luthar & Ansary, 2005).These empirical findings – based on youth who attend schools with higher than average standardized test scores, rich extracurricular and college-level academic offerings, and graduates who are typically admitted to selective colleges (Luthar et al., 2020a; Luthar et al., 2020b; Stiles et al., 2020) – have led developmentalists and policy researchers to identify HAS as one of the top high-risk environments for youth (Geisz & Nakashian, 2018; National Academies of Science Engineering and Medicine, 2019).
Guided by ecological models of youth risk and resilience (e.g., Bronfenbrenner, 1977; Vélez-Agosto et al., 2017) which argue that youth developmental outcomes depend, in part, on the context in which they are located, Luthar and colleagues (2020) propose that the confluence of unrelenting pressures to achieve from the HAS youths’ microsystem (i.e., schools, parents, and peers) proximally contribute to their elevated problem behaviours. In support of this argument, prior research based on HAS youth from different cohorts and varying locations within the United States (U.S.) indicates that these youth are typically exposed to multiple contextual pressures, specifically excessive academic demands, parent-related stressors, and extensive social comparisons among peers, which can negatively impact their adjustment (Luthar et al., 2020a).
The problematic context of HAS for youth and families
While many HAS youth are from families with relatively high socioeconomic backgrounds, some are from families of less wealthy backgrounds but are exposed to the same high pressure context (Lund & Dearing, 2013; Lyman & Luthar, 2014). One such pressure is excessive academic demands. Because the competition to meet the perceived thresholds of success is keen (e.g., admission to highly-selective colleges), HAS youth need to excel in multiple scholastic and extracurricular domains to distinguish themselves from their peer group in school (Leonard et al., 2015; Spencer et al., 2016). The stress associated with these academic demands and associated pressures to perform place HAS youth at increased risk for adjustment problems (Luthar & Barkin, 2012; Randall & Bohnert, 2012).
HAS youth also generally have parents who are highly educated with lucrative white-collar careers, and have lofty aspirations for their children. These aspirations can manifest as high performance standards (e.g., parent criticism) with an overemphasis on material achievement (Ciciolla et al., 2017; Davis-Kean, 2005), and a tendency to be over-protective or overly-involved in their children's lives (Levine, 2006). Moreover, due to their demanding work commitments, these parents can be physically and emotionally disengaged from their children (e.g., Kushlev et al., 2012). Such parenting behaviours have been associated with depression, anxiety, and risky behaviour in late adolescence and emerging adulthood (Bradley-Geist & Olson-Buchanan, 2014; LeMoyne & Buchanan, 2011; Luthar & Becker, 2002).
Comparisons among peers are common in adolescence. However, when coupled with heightened competition among similarly abled, highly-resourced peers, social status comparisons can place youth at greater risk for problem behaviours (Li et al., 2021; Pekrun et al., 2019). Prior studies indicate that across three different HAS samples in the U.S., social comparisons were associated with internalizing problems (Luthar et al., 2020b), supporting previous work that suggests HAS youth may be more vulnerable to the negative consequences of peer envy and social comparisons because of their perfectionistic tendencies (Lyman & Luthar, 2014).
While the “HAS” argument is compelling, research on the effects of HAS on youth adjustment is limited to studies from individualistic-oriented, Western societies, such as the U.S. (Luthar et al., 2020a). This gap in the literature is problematic as eco-cultural perspectives on youth adjustment suggest that the risk for problem behaviours may differ across cultural context (i.e., macrosystem) (Coll et al., 2000). Therefore, this pattern of elevated risk for adjustment problems among HAS youth may not generalize to collectivistic-oriented, non-Western settings. To address this concern, the current study explored whether adolescents from HAS schools in Hong Kong (1) showed preliminary indication of elevated risk for internalizing and externalizing problems as observed in Western societies, and (2) if the previously established contextual risk factors, namely excessive academic demands, parent-related stressors, and extensive social comparisons among peers, were associated with these problems.
Hong Kong families were of particular interest for three reasons. First, the education systems in many Asian countries, including Hong Kong, are thought to be highly competitive and stress-inducing (Komatsu & Rappleye, 2018; Tan, 2018). If HAS do confer similar risks to youth adjustment in Asian societies, it could have significant implications for schools and school-based professionals providing support to these youth. Second, while some studies have examined the adjustment of Hong Kong adolescents (Chen & Kuo, 2020; Shek & Siu, 2019; Shek & Zhu, 2018), no known study has focused on high-achieving private schools in Hong Kong whose students compete at a global level with HAS youth from Western societies and attend many of the same selective universities. Third, Hong Kong adolescents serve as an interesting sample to test the universality or cultural specificity of previously identified contextual risk factors for HAS youth. Although Hong Kong is a modern, cosmopolitan society with strong British influence, traditional Confucian-influenced Asian values remain a dominant socializing force (Leung et al., 2009; Oyserman et al., 2002). Risk factors that contribute to problem behaviours in an individualistic-oriented cultural context may be considered normative in Hong Kong and not confer the same risks to youth adjustment (e.g., Bornstein, 2012). For example, if excessive academic demands or over-protective parenting behaviour are considered typical youth experiences in collectivistic-oriented settings (Chao & Tseng, 2002; Kwon et al., 2017; Wu et al., 2002), they may not have the same negative implications for HAS youth adjustment.
Method
Participants
Participants were a convenience sample of 237 adolescents (64.5% females; 14–18 years old; Mage = 15.8) and one of their parents (68.8% mothers; 35–65 years old; Mage = 49.4) who were recruited from four high-achieving private schools in Hong Kong. The average IB scores at these schools ranged from 36.1–37.9 as compared to the global average of 29.8 in 2018. About 30 to 40% of the students in these schools achieved at least 40 out of 45 points on the IB exam. On average, less than 10% of students worldwide achieve these scores (International Baccalaureate, 2018). Most adolescents identified as Chinese (65.0%); the rest identified as Bi-racial (e.g., either mixed-Asian or mixed Asian-White: 16.0%), White (9.70%), and of other East Asian (e.g., Korean, Japanese: 5.5%) or South Asian ethnicity (e.g., Indian, Pakistani, Nepalese: 3.8%). 1
Families’ median monthly household incomes ranged from HKD$100,000 to $150,000 (US$12,860 – $19,300). The national median monthly household income at the outset of data collection was HKD$25,000 (∼US$3,215) (Census and Statistics Department, 2017). Over 80% had at least twice the median monthly household income (HK$50,000 and above). Most fathers (83.1%) and mothers (71.3%) completed at least a college-level education and were employed in senior executive, managerial, or qualified professional level positions (86.9% fathers; 50.6% mothers).
Procedure
The cross-sectional data were collected between November 2016 and April 2017, prior to the COVID-19 pandemic and the 2019–2020 Hong Kong protests. The first author and trained research assistants administered the surveys in English, the schools’ language of instruction, to the adolescents in their classrooms. Parent surveys in their preferred language (i.e., English or traditional Chinese; the latter were translated and back-translated by native speakers for accuracy) were completed at home and returned to the first author in sealed envelopes via mail or the schools. Parent consent and youth assent were obtained. Except for an ID code linking parent-adolescent dyads, the surveys were anonymous. No monetary incentives were offered. All procedures were approved by the University of Southern California's Institutional Review Board [UP-16-00394].
Measures
Demographic questionnaire
Sociodemographic information was provided by adolescents (i.e., adolescent age, adolescent gender, adolescent ethnicity) and their parent (i.e., parent age, parent gender, parent ethnicity, family's monthly household income, and parents’ highest levels of education and occupations).
Youth internalizing and externalizing problems
Parents completed the 120-item Child Behavior Checklist (CBCL/6-18; Achenbach & Rescorla, 2001) and adolescents rated the parallel 112-item Youth Self-Report (YSR; Achenbach & Rescorla, 2001) to assess youth emotional and behavioural problems. The CBCL and YSR comprise two broadband scales: internalizing (anxious-withdrawn, anxious-depressed, somatic complaints) and externalizing problems (rule-breaking, aggressive behaviours). They have strong psychometric properties and well-established cross-cultural generalizability across diverse populations (Ivanova et al., 2007a; Ivanova et al., 2007b), including Hong Kong (Leung et al., 2006). In the current study, the CBCL (internalizing α = .86; externalizing α = .80) and YSR (internalizing α = .90; externalizing α = .86) showed good reliability.
Academic demands
Adolescents completed the 13-item Academic Requirements (AR) subscale of the Student Rating of Environmental Stressors Scale (StRESS; Suldo et al., 2014), with items related to academic stress, including “Large amount of homework,” “Too little time (feeling like there are ‘not enough hours in the day’)” and “Overly high expectations for achievement” (1 = never; 5 = almost always). The StRESS is a measure of contextual stressors experienced by students who are engaged in accelerated high school curricula, such as Advanced Placement (AP) and International Baccalaureate (IB) courses. Reliability was α = .88.
Parent-related stressors
Adolescents completed the 6-item Parent-Child Conflict (PCC) subscale of the StRESS (Suldo et al., 2014) with items related to parenting behaviours, including “Parents’ overly high expectations for achievement,” “Parents too involved with school,” and “Parents not understanding your school experiences and/or demands.” Reliability was α = .83.
Social status among peers
Adolescents rated a modified version of the MacArthur Scale of Subjective Social Status (Adler et al., 1994). They were shown a 10-rung ladder and asked to imagine that it was a way to represent their school, with people at the top of the ladder being those in their school with the most respect, the highest grades, and the highest school standing; and people at the bottom being those who no one respects, no one wants to hang around with, and have the worst grades. Adolescents were then asked where they would place themselves on the ladder using a 10-point scale (top of the ladder = 1; bottom of the ladder = 10). The scores of this single-item measure were reverse-coded for data analysis.
Results
Descriptive analyses
Means and standard deviations for the key variables and the correlation matrix of the variables are provided in Tables 1 and 2.
Means and standard deviations for the key variables by sample and gender (N = 237).
Note. a Family income range: 1 = HKD$0–25,000 to 6 = above HKD$150,000; average monthly household income was between (4) HKD$75,001–100,000 and (5) $100,001–150,000.
Range of Parents’ Education: 1 = completed some primary/elementary education to 10 = Ph.D., law, or medical degree; average highest level of education for fathers and mothers was between bachelor's degree (7) to some postgraduate work (8).
*p ≤ .05 (2-tailed), **p ≤ .01 (2-tailed), ***p ≤ .001 (2-tailed).
Correlations among the key variables (n = 237).
Note. Gender: 1 = male, 2 = female.
*p ≤ .05 (2-tailed), **p ≤ .01 (2-tailed), ***p ≤ .001 (2-tailed).
Proportion of youth with borderline-clinical and clinical levels of problem behaviors based on Hong Kong norms
Supplemental Tables I and II show the proportions of adolescents and parents who reported youth problem behaviours that fell above borderline-clinical (≥ 86%ile) and clinical levels (≥ 98%ile) based on Hong Kong societal norms. The criteria was based on Hong Kong normative scores from the Multicultural Supplement to the Manual for ASEBA School-Age Forms and Profiles (Group 3 for YSR and Group 2 for CBCL; Achenbach & Rescorla, 2007), which were derived from data collected on three different samples (i.e., school, clinic, and community) in Hong Kong (Leung et al., 2006). The normative scores used are the suggested formal, clinical criteria for scoring the CBCL and YSR with Hong Kong samples (Achenbach & Rescorla, 2001, 2007).
For internalizing problems, 45.8% of the female adolescents and 38.1% of the males reported at least borderline-clinical levels of internalizing symptoms, and 29.4% of the females and 21.4% of the males met clinical levels for youth-reported internalizing problems. Parents reported that 26.8% of the female adolescents and 14.3% of the males showed at least borderline-clinical levels of internalizing problems, and 19.6% of the females and 9.5% of the males had clinical levels of internalizing problems. Previous mainstream school- and community-based studies of Hong Kong adolescents indicate that the prevalence for depression is between 0.55% and 2.2% and the prevalence for anxiety is between 2.6% and 6.9% (Yuen et al., 2019).
For externalizing problems, 12.4% of female adolescents and 7.1% of males reported at least borderline-clinical levels of externalizing symptoms. Significantly more females (6.5%) than males (0.0%) met clinical criteria for youth-reported externalizing problems. Parents reported that 9.8% of female adolescents and 3.6% of males showed borderline-clinical levels of externalizing problems, and 5.9% of females and 1.2% of males met clinical levels. Prior studies indicate that the prevalence of specific risky and delinquent behaviours (excluding cheating and using foul language 2 ) for youth from the general secondary school population in Hong Kong range from 1.1–14.5% for rule breaking behaviours, such as truancy, stealing, and property damage and 3.3% - 29.1% for aggressive behaviours, such as beating or bullying others and gang-related activities (Lau & Kan, 2010; Shek & Zhu, 2018).
Contextual predictors of youth problem behaviors
Multiple linear regressions tested whether academic demands, parent-related stressors, and social status among peers were associated with youth internalizing and externalizing problems, after controlling for age and gender (Tables 3 and 4).
Results of multiple regression for risk factors predicting internalizing problems (n = 237).
Note. *p ≤ .05 (2-tailed), **p ≤ .01 (2-tailed), ***p ≤ .001 (2-tailed).
Results of multiple regression for risk factors predicting externalizing problems (n = 237).
Note. *p ≤ .05 (2-tailed), **p ≤ .01 (2-tailed), ***p ≤ .001 (2-tailed).
The model significantly predicted youth-reported internalizing problems, F(5, 231) = 34.48, p ≤ .001, and explained 42.7% of the variance in outcomes. Academic demands (β = .28, p ≤ .001), parent-related stressors (β = .34, p ≤ .001), and social status among peers (β = − .29, p ≤ .001) significantly contributed to the model (Table 3). The model also predicted parent-reported internalizing problems, F(5, 231) = 8.78, p ≤ .001, with parent-related stressors (β = .22, p = .003) and social status among peers (β = − .22, p ≤ .001) significantly contributing to youth outcomes. However, the model only explained 16.0% of the variance in adolescent outcomes.
The model significantly predicted both youth-reported, F(5, 231) = 19.85, p ≤ .001, and parent-reported, F(5, 231) = 5.61, p ≤ .001, externalizing problems and explained 30.1% and 10.8% of the variance in outcomes, respectively (Table 4). Only parent-related stressors significantly predicted youth-reported (β = .52, p ≤ .001) and parent-reported (β = .31, p ≤ .001) externalizing problems.
Discussion
The current study is the first-known study to explore contextual predictors related to problem behaviours among youth who attend high-achieving private schools in a collectivistic-oriented setting. Overall, the results preliminarily indicate that HAS youth in Hong Kong may be at elevated risk for internalizing problems and protected against externalizing problems. This finding contrasts with research from the U.S. that showed HAS youth were at increased risk for both internalizing and externalizing problems (e.g., Luthar & Becker, 2002), and underscores the importance of considering the cultural context when studying the effects of achievement pressures.
One possible explanation for this difference in risk pattern may be related to cultural variations in peer norms. That is, while Hong Kong youth face similar pressures to achieve academically as do their HAS peers in individualistic-oriented Western societies; they may be less pressured by their peers to engage in substance use and other rule-breaking behaviours. Externalizing behaviours are often associated with increased popularity within peer groups in the U.S.; however, HAS adolescents in Hong Kong may be less inclined to engage in these behaviours because popularity among collectivistic-oriented Asian youth is more strongly associated with prosocial behaviours and academic achievement than with antisocial behaviours (Niu et al., 2016). Such variations in the manifestation of risk among youth may be observed in other cultural settings with similar value systems.
The results also showed that more females than males met clinical criteria for self-reported externalizing problems and parent-reported internalizing problems. This variation in risk status may be associated with gender-typed behavioural norms where females are typically held to higher behavioural standards than are males (e.g., Spencer et al., 2016). They also face more peer pressure to be popular and conformity to social norms than are males (e.g., Jones et al., 2004). Research on Asian youth supports the existence of gendered experiences. Compared to their male peers, Mainland Chinese female adolescents worry more about their grades and have higher self-expectations (Sun et al., 2013). Moreover, Chan et al. (2011) found that while females in Hong Kong believe that they should be allowed to pursue their dreams and be independent like their male peers, they are also expected to adhere culturally normative ‘feminine’ behaviours such as looking presentable and having good manners. This pressure to succeed in multiple gendered roles may contribute to heightened distress among females in societies that maintain these stereotypical gendered roles (Tang & Tang, 2001).
Of note was the higher proportion of females who met borderline clinical or clinical criteria for externalizing problems relative to males. There are three possible explanations for this finding. First, because internalizing and externalizing problems are highly co-morbid, the elevated stress levels experienced by HAS females may place them at greater risk for both problem behaviours compared to their male peers (Fanti & Henrich, 2010; McConaughy & Skiba, 1993). Second, studies suggest that self-critical cognitions are positively associated with comorbid externalizing problems (Ferguson et al., 1999).Therefore, if HAS females are more concerned with embodying moral and behavioural correctness than their male peers (Wang & Leichtman, 2000), then the self-criticism that follows when they are not able to achieve these internalized expectations could make them more vulnerable to externalizing problems. Finally, emerging research suggests than young women are more likely than men to turn to substance use, particularly alcohol, to cope with stress, thus increasing their overall vulnerability to externalizing problems (Norberg et al., 2010; Rice & Van Arsdale, 2010). Future research should examine these and other potential explanatory mechanisms for variations in risk.
Consistent with prior research on cross-informant discrepancy (De Los Reyes & Kazdin, 2005) and underreporting of problem behaviours by Asian parents due to poor mental health literacy and mental health stigma within these communities (Lau & Takeuchi, 2001; Wang et al., 2019), the study found that the proportion of youth who met borderline-clinical and clinical criteria for internalizing problems based on parent reports was only about half the proportion of those who met these criteria based on self-report. Because youth depend on the adults in their lives to recognize problems and engage them in treatment, this raises the question as to whether Hong Kong HAS youth considered “at risk” – and indeed HAS youth from other similar cultural settings with low mental health literacy or high mental health stigma – obtain the help they need (Wahlin & Deane, 2012).
Our findings on contextual predictors associated with HAS youth adjustment were generally consistent with extant research (Luthar et al., 2020a). Academic demands, parent-related stressors, and social status among peers, significantly predicted over 40% of the variance in youth-reported internalizing problems. Parent-related stressors also predicted externalizing problems; however, in contrast to findings from U.S. samples (Luthar & Becker, 2002; Lyman & Luthar, 2014; Moroney et al., 2022), social status among peers did not. This finding further supports our earlier discussion that cultural differences in the perceived social value of externalizing behaviours between individualistic- and collectivistic-oriented HAS youth may mitigate Hong Kong HAS youth risk for delinquent and substance use problems.
As found in previous studies, parent-related stressors were the most consistent predictor of problem behaviours among our sample. This finding suggests that perceived parental pressure and parent-child relations are more proximal risk mechanisms than excessive academic demands or social status among peers (Luthar et al., 2006; Randall et al., 2015). Parents who have overly high expectations for achievement and are excessively involved in children's lives, place undue pressure on youth and inadvertently interfere with key developmental tasks of adolescence, such as independent problem-solving and decision-making, which negatively impact youths’ resilience in crisis situations (Levine, 2006). As culture shapes parenting behaviour and the relative impact on youth outcomes, future research should identify specific parent behaviours that contribute to problem behaviours among HAS youth in other collectivistic-oriented Asian settings, as well as how the HAS context influences parent behaviours.
Limitations
Several limitations should be acknowledged. First, because there were no comparison groups, explicit conclusions cannot be drawn about differences between Western and Hong Kong youth or between HAS and non-HAS Hong Kong youth. However, we used the CBCL and YSR, which are “gold standard” child and adolescent assessments for behavioural problems, using norms derived for Hong Kong society which provided a strong indication of youth risk. The findings thus serve as an important starting point to develop a research programme to examine culturally-relevant risk factors for this population.
Second, our sample was a convenience sample of private school students from relatively affluent background. Hence, participants may not represent the full spectrum of HAS adolescents in Hong Kong. To ensure generalizability it is necessary to replicate the study with a larger community sample of varying socioeconomic status and those from public HAS schools. Nonetheless, participants were recruited from four different high-achieving private schools across different areas of Hong Kong (e.g., Hong Kong Island and the New Territories), mitigating some concerns about sample representativeness. Future research should also consider studying HAS youth from other Asian countries, which have similarly competitive and stressful education systems.
Third, parents and youth may not have reported aggressive or rule-breaking youth behaviours that violate acceptable norms or may negatively impact a youth's future in some fashion. To reduce social desirability bias, participants were repeatedly assured that their survey responses were anonymous; they were also not explicitly informed that the study focused on youth problem behaviours.
Fourth, because of the cross-sectional research design, we cannot draw conclusions about causality or the long-term impact of elevated risk. While parent-related stressors may promote behavioural problems in youth, it is also plausible that youth who are anxious, depressed, or oppositional are inclined to perceive the world in a more negative light. Longitudinal research would help to clarify the cause and impact of these risks.
Implications
The study's findings have three practical implications. First, because HAS adolescents do not fit the traditional profile of youth deemed to be “at risk,” it is important to raise awareness of their elevated risk status among school psychologists, teachers and school administrators who are responsible for risk screening and providing support to these youth. Second, because parents play a key role in the adjustment of HAS youth, HAS should develop collaborative programmes that engage parents as major partners. However, these interventions should be contextually relevant. While stress and ineffective parenting may be a universal risk factors for all youth, the types of stress and parenting practices that affect HAS adolescents may differ from those from non-HAS and interventions should be modified to reflect this situation. Finally, although parent-related stressors consistently predict problem behaviours among HAS youth, our findings indicate that academic demands and social comparisons among peers also contribute to the risk model. Hence, HAS should focus on creating school climates that do not overvalue competition and material success, and focus instead on prosocial behaviours and youth well-being. In doing so, they may be able to mitigate some of these risks to youth adjustment.
Conclusion
Attending a HAS is typically associated with many educational benefits, such as access to a greater variety of learning and extracurricular resources, higher standardized test scores and college enrolment, and more income and occupational prestige later in life (Allensworth et al., 2016; Göllner et al., 2018). However, it appears that for many Hong Kong youth, particularly females, attending a HAS also yields significant risks to their adjustment. This is problematic as such challenges to youth well-being can significantly impact their long-term productivity and mental health, and undercut the material benefits of attending a HAS. Because our understanding of the contextual risks faced by HAS youth is still quite preliminary, more work is needed to identify how we can better intervene and enhance the resilience of these youth.
Supplemental Material
sj-docx-1-spi-10.1177_01430343221133499 - Supplemental material for Contextual predictors of internalizing and externalizing problems among adolescents from high-achieving private schools in Hong Kong
Supplemental material, sj-docx-1-spi-10.1177_01430343221133499 for Contextual predictors of internalizing and externalizing problems among adolescents from high-achieving private schools in Hong Kong by Jacqueline L. Tilley and JoAnn M. Farver in School Psychology International
Footnotes
Acknowledgements
We would like to thank Stanley Huey, Steven Lopez, David Schwartz, Erika Patall, Cammie McBride, and Robert Rueda for their useful feedback and assistance on the study. We are also grateful to all the families and schools who participated in the study.
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the University of Southern California, (University of Southern California Graduate School)
Ethical approval
All procedures were approved by the University of Southern California Institutional Review Board [UP-16-00394]. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent
Informed parental consent and adolescent assent was obtained from all participants included in the study.
Data availability
The data that support the findings of this study are available from the corresponding author, upon request.
Supplemental material
Supplemental material for this article is available online.
Notes
Author biographies
References
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