Adolescence: a vulnerable developmental phase
Adolescence is a crucial developmental phase characterised by notable physical, emotional and cognitive transformations, which makes young people particularly susceptible to mental health problems, namely anxiety and depression.Reference Blakemore1 Recent estimates indicate that each year about 20% of adolescents worldwide experience mental health problems, mostly depression and anxiety, with these conditions sometimes persisting into adulthood.Reference Clayborne, Varin and Colman2 Given the significant impact of these disorders on adolescents’ quality of life, academic performance and future psychosocial adjustment,Reference Agnafors, Barmark and Sydsjö3 there is a critical need for a deeper understanding of their aetiology and contributing factors.
During adolescence, individuals often experience an intensified focus on self-identity, self-concept and self-acceptance.Reference Garcia and Vassar4 Furthermore, adolescence marks a time when social comparison becomes particularly salient, partly owing to increased significance of peer relationships and a heightened awareness of social hierarchies.Reference Roseth, Johnson and Johnson5 These evolving dynamics around self-perception and social evaluation intersect with broader psychosocial elements, such as attributional styles, that also undergo critical developmental shifts during adolescence. Therefore, understanding the complex relationships between self-acceptance, social comparison and mental health outcomes such as depression and anxiety becomes especially crucial at this stage.
Self-acceptance, social comparison and attributional style
Self-acceptance and social comparison, which are both fundamental components of adolescents’ psychological functioning, have been identified as significant correlates of adolescent mental health.Reference Sanghvi, Zainal and Newman6 Self-acceptance, defined as an individual's acceptance of themselves, including their strengths and weaknesses, has been linked to better psychological well-being and lower levels of anxiety and depression.Reference Huang, Wu, Wu, Yang, Zheng and Wu7 Self-acceptance is understood as a fundamental component of psychological health, as it relates to an individual's ability to embrace their unique qualities, including strengths and weaknesses.Reference Pepping, Cronin, Halford and Lyons8 One studyReference Neff9 suggested that self-acceptance is integral to mental health, as individuals with higher levels of self-acceptance are typically more resilient in the face of stress and adversity. Moreover, research has consistently demonstrated a negative correlation between self-acceptance and mental health problems such as depression and anxiety.Reference Sanghvi, Zainal and Newman6 For instance, one studyReference Sowislo and Orth10 revealed that individuals with low self-acceptance levels tend to experience more negative emotions, including depressive and anxious symptoms, signifying the protective role of self-acceptance against mental health problems.
On the other hand, social comparison, defined as the process of comparing oneself with others, has been linked to psychological distress. FestingerReference Festinger11 proposed the social comparison theory, suggesting that individuals inherently have a drive to assess their abilities and opinions, which is often done by comparing themselves with others. The negative psychological effects of social comparison can be especially potent during adolescence, a developmental period characterised by heightened peer comparison and approval-seeking behaviours.Reference Coyne, McDaniel and Stockdale12 Research suggests that unfavourable social comparison can lead to feelings of inferiority, envy and dissatisfaction, which may increase the risk of developing symptoms of depression and anxiety.Reference Buecker, Maes, Denissen and Luhmann13,Reference Gibbons and Buunk14
These relationships could be complicated by other individual differences, such as attributional style. Attributional style theory, initially proposed by Weiner,Reference Weiner15 suggests that the way people explain the causes of events, as being internal or external, has a significant impact on their emotional well-being. This theory has been supported by several studies. For instance, Peterson et alReference Peterson, Semmel, von Baeyer, Abramson, Metalsky and Seligman16 found that children and adolescents who made more internal attributions (attributing events to factors within themselves) for negative events were more likely to exhibit symptoms of depression. Further, research conducted by Sweeney et alReference Sweeney, Anderson and Bailey17 suggested that individuals who attribute negative events to external factors – outside of their control – tend to report higher levels of stress and anxiety. This is consistent with the learned helplessness theory, which suggests that people who consistently attribute negative events to uncontrollable factors may begin to feel helpless, leading to depression and anxiety.Reference Peterson and Seligman18 A study by Kleim et alReference Kleim, Gonzalo and Ehlers19 showed that trauma survivors with higher levels of external attributions for their trauma were more susceptible to developing post-traumatic stress disorder, a type of anxiety disorder. Similarly, a meta-analysis conducted by Joiner & WagnerReference Joiner and Wagner20 found a significant association between external attributional style and depressive symptoms across numerous studies.
Bridging the research gap: an integrated perspective
Despite the substantial body of research showing the influence of self-acceptance and social comparison on mental health, notably depression and anxiety, a conspicuous gap exists in our understanding of the complex interplay among these variables, particularly during the crucial period of adolescence. This gap is twofold.
First, most studies to date have treated self-acceptance and social comparison as separate influences on mental health, with limited research investigating the potential mediating role of social comparison in the relationship between self-acceptance and mental health outcomes. Studies have established that higher self-acceptance is associated with better mental healthReference Neff21,Reference Wood, Maltby, Gillett, Linley and Joseph22 and that negative social comparison can lead to feelings of inferiority and subsequent mental health problems.Reference Festinger11,Reference Buecker, Maes, Denissen and Luhmann13 However, the relationship between these variables remains unclear. For instance, does low self-acceptance lead to negative social comparison, which in turn contributes to depression and anxiety? Or do low self-acceptance and negative social comparison independently contribute to these mental health problems? A deeper understanding of these relationships could lead to more effective interventions, by identifying key targets (e.g. promotion of self-acceptance, teaching healthier social comparison strategies) that could alleviate adolescent depression and anxiety.
Second, there is a dearth of research investigating how these relationships may be moderated by individuals’ attributional tendencies. Attributional style, or how individuals interpret the causes of events, has been linked with various mental health outcomes, including depression and anxiety.Reference Peterson and Seligman18,Reference Abramson, Metalsky and Alloy23 Specifically, an external attributional style – attributing outcomes to factors outside oneself – has been associated with feelings of helplessness and increased mental health problems.Reference Peterson and Seligman18 It is plausible that adolescents with an external attributional style may be particularly prone to the negative effects of low self-acceptance and negative social comparison. For instance, individuals with an external attributional style may be more likely to engage in detrimental social comparisons and have lower self-acceptance, thereby increasing their risk of mental health consequences.Reference Buecker, Maes, Denissen and Luhmann13 Conversely, those with an internal attributional style, who attribute events to their own actions, may engage in more adaptive social comparison strategies and demonstrate higher levels of self-acceptance, thus potentially protecting against depression and anxiety.Reference Wood, Linley, Maltby, Baliousis and Joseph24 However, to the best of our knowledge, no study has yet examined the potential moderating function of attributional style in these associations.
Given the developmental stage under investigation, we contend that self-acceptance serves as the primary mover. As adolescents negotiate their evolving identities, self-acceptance becomes the cornerstone of their intrapsychic world, providing the lens through which they interpret their self-worth. Identity formation is at the forefront during this life stage.Reference McLean and Breen25 It is this internal state of self-acceptance that then influences the manner and extent to which adolescents engage in social comparison. Hence, we chose to model self-acceptance as the predictor and social comparison as the mediator, grounded in developmental psychology theory. To address these gaps, it is critical to conduct studies that explore the mediating role of social comparison in the relationship between self-acceptance and mental health outcomes, while also considering the potential moderating effect of attributional style. Such research would not only contribute to the theoretical understanding of these constructs, but also potentially guide the development of targeted interventions to enhance mental health among adolescents.
Method
Participants
A total of 242 adolescent out-patients were selected by convenience to receive one-on-one mental health assessments. Prior to the mental health assessment, the patients and their parents/guardians were informed about the assessment procedure and scales to be used and both a parent/guardian and the patient provided written informed consent, as required by local hospital ethics regulations. The mean age of the participants was 14.96 years (s.d. = 1.54 years). The sample comprised 81 (33.47%) males and 161 (66.53%) females; 71 participants (29.34%) had a foster or ‘left-behind’ experience in their past; 57 participants (23.55%) were from incomplete families. In terms of attributional tendency, 147 participants (60.74%) had an internal attributional tendency and 95 (39.26%) had an external attributional tendency (Table 1).
Measures
Demographic information
Basic demographic information about each adolescent, such as gender, age, whether they had any experience of being left behind and family structure, were recorded. Gender (female versus male), left-behind experience (left-behind versus not left-behind), family structure (complete or incomplete) were coded as binary variables.
Attributional styles
The Multidimensional-Multiattributional Causality Scale (MMCS)Reference Lefcourt, von Baeyer, Ware and Cox26 was utilised to assess participants’ attributional styles related to achievement. The 24-item Achievement Locus of Control subscale was selected for this study. Each item is rated on a 5-point Likert scale from 0 (disagree) to 4 (agree), with higher scores indicating higher degrees of endorsement for a particular attributional tendency. Where an internal attribution score was greater than or equal to an external attribution score, this was coded as an internal attributional tendency, and vice versa. Previous research also found the MMCS to have good construct and convergent validity, with Cronbach's α = 0.83.Reference Kong, Chen, Shen, Li, Gao and Zhu27 In the present study, the Cronbach's α for the MMCS Achievement subscale was 0.84, indicating good reliability for use with this sample.
Self-acceptance
Self-acceptance was measured using the Self-Acceptance Questionnaire (SAQ), a 16-item measure comprising two subscales: Self-Acceptance and Self-Evaluation.Reference Cong and Gao28 The Self-Acceptance subscale includes eight reverse-scored items rated on a 4-point Likert scale from 1 (strongly disagree) to 4 (strongly agree). The Self-Evaluation subscale includes eight positively worded items, also rated on a 4-point Likert scale from 1 (strongly disagree) to 4 (strongly agree). Subscale scores were summed, with higher scores indicating greater self-acceptance. In the current study, the SAQ demonstrated good internal consistency, with Cronbach's α = 0.89.
Social comparison
Social comparison was assessed using the 11-item Iowa–Netherlands Comparison Orientation Measure (INCOM),Reference Gibbons and Buunk14,Reference Buunk and Gibbons29 a widely used measure of individuals’ tendency to compare themselves with others. Each INCOM item is scored on a 5-point Likert scale from 1 (strongly disagree) to 5 (strongly agree). Higher total scores reflect a greater social comparison orientation. Previous research found the INCOM to be a reliable and valid measure of social comparison tendencies in diverse populations.Reference Gibbons and Buunk14 In the present study, the INCOM demonstrated good internal consistency (Cronbach's α = 0.82).
Depression
Depressive symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9),Reference Kroenke, Spitzer and Williams30 a 9-item measure derived from the DSM-IV criteria for major depressive disorder. Each PHQ-9 item is rated on a 4-point Likert scale from 0 (not at all) to 3 (nearly every day), with total scores ranging from 0 to 27. Higher scores indicate greater severity of depressive symptoms. A total score ≥15 was used to identify cases of likely major depressive disorder, providing good specificity for diagnosis.Reference Kroenke, Spitzer and Williams30 Previous research shows the PHQ-9 to have good validity and reliability in both clinical and community populations. In the present study, the PHQ-9 demonstrated high internal consistency, with Cronbach's α = 0.92.
Anxiety
Generalised anxiety disorder symptoms were assessed using the 7-item Generalized Anxiety Disorder scale (GAD-7).Reference Spitzer, Kroenke, Williams and Löwe31 The GAD-7 asks participants to rate how often they have been bothered by anxiety symptoms over the previous 2 weeks on a 4-point Likert scale from 0 (not at all) to 3 (nearly every day). Total scores range from 0 to 21, with higher scores indicating greater anxiety severity. A score ≥10 has been established as a cut-off for likely diagnosis of generalised anxiety disorder. Previous research shows the GAD-7 to have good reliability and validity for screening anxiety in clinical practice and research.Reference Ruiz, Zamorano, García-Campayo, Pardo, Freire and Rejas32 In the present study, the GAD-7 showed excellent internal consistency, with Cronbach's α = 0.94.
Statistical analysis
Statistical analyses were performed using SPSS Version 23.0 and R Version 4.2.1 for Windows. SPSS was used for initial data entry and exploratory analyses. R was used specifically for mediation modelling. First of all, descriptive statistics and reliability analyses were conducted. Second, independent samples t-tests compared scores on depression, anxiety, self-acceptance and social comparison measures across external and internal attribution subgroups. Separate t-tests were run for each variable, with α set at 0.05. Cohen's d was calculated as an estimate of effect size, with 0.20 constituting a small effect, 0.50 a medium effect and 0.80 a large effect.Reference Wright, Robin, Rhee, Vaculin, Jacks and Guenther33 Third, mediation models were constructed to determine whether social comparison mediated the relationship between self-acceptance and depression/anxiety symptom severity. Direct and indirect effects were estimated using the product method, with 95% bias-corrected confidence intervals derived from 1000 bootstrap samples. Indirect effects were considered significant where the confidence interval did not cross zero. Finally, a multi-group structural equation model was constructed to test whether this mediation model differed significantly across external and internal attribution subgroups. Separate mediation models were specified for each subgroup, and model fit was compared to determine whether freeing or constraining certain pathways across groups resulted in significantly better fit using the χ2 difference test.Reference Preacher and Hayes34 A non-significant χ2 difference would indicate that the pathway could be constrained to be equal across groups; a significant χ2 difference would indicate that the pathway should be freely estimated, suggesting group differences. Significant differences in specific mediation pathways between external and internal attribution groups were then explored by calculating the critical ratio of difference (CRd). If the absolute value of the CRd is higher than 1.965, then there is an intergroup difference at the level of P < 0.05.Reference Preacher and Hayes34
Ethics approval and consent to participate
The authors assert that all procedures contributing to this work comply with the ethical standards of the relevant national and institutional committees on human experimentation and with the Helsinki Declaration of 1975, as revised in 2008. All procedures involving human subjects/patients were approved by the institutional review board of Wenzhou Seventh People's Hospital (EC-KY-2022048).
Results
Descriptive statistics for the measurements of the 242 participants are shown in Table 2. Self-acceptance and social comparison were both significantly associated with anxiety and depression (P < 0.001), left-behind experience and family structure were significantly associated with depression (P < 0.05) and left-behind experience was significantly associated with anxiety (P < 0.05). Independent samples t-tests showed that individuals with external attributional tendencies reported higher levels of depression and anxiety than those with internal attributional tendencies. More specifically, it was found that depression scores were significantly higher in the external attribution group (mean 17.73, s.d. = 6.80) than in the internal attribution group (mean 12.90, s.d. = 8.61) (t = 4.61, P < 0.001, Cohen's d = 0.61). Anxiety scores were also significantly higher in the external attribution group (mean 13.91, s.d. = 5.88) than in the internal attribution group (mean 9.97, s.d. = 7.23) (t = 4.44, P < 0.001, Cohen's d = 0.58).
*P < 0.05, **P < 0.01, ***P < 0.001.
Mediated model
Multiple regression analysis (Table 3) was conducted to examine the mediating role of social comparison in the relationships between self-acceptance and anxiety/depression. Age, gender, foster and left-behind experience, and family structure were included as covariates. The analysis revealed that social comparison was negatively predicted by self-acceptance (β = −0.33, P < 0.001), indicating that lower self-acceptance was associated with higher social comparison tendencies. Depression was negatively predicted by self-acceptance (β = −0.67, P < 0.001) and positively predicted by social comparison (β = 0.11, P < 0.01). Anxiety was negatively predicted by self-acceptance (β = −0.49, P < 0.001) and positively predicted by social comparison (β = 0.18, P < 0.001). A mediation analysis was conducted to assess whether social comparison mediated the relationships between self-acceptance and both depression and anxiety symptoms. The results supported that social comparison significantly mediated the links between self-acceptance and both depression and anxiety symptoms (Table 4). Self-acceptance had indirect effects on depression (effect size −0.04, 95% CI −0.06 to −0.02) and anxiety (effect size −0.06, 95% CI −0.10 to −0.02) through social comparison. Lower self-acceptance predicted higher social comparison, which in turn predicted higher levels of depression and anxiety symptoms.
β, standardised coefficient.
Group difference test
To investigate whether the mediated relationships differed by attributional tendency, multi-group analyses were conducted (Table 5). The free model allowed all path coefficients to differ between external and internal attribution groups. The constrained model held path coefficients equal between groups. The result of chi-squared testing highlighted a significant difference between the free model and constrained model (depression: Δχ2(3) = 8.40, P < 0.05; anxiety: Δχ2(3) = 8.68, P < 0.05). This indicates that the path coefficients in the mediation model differed significantly between external and internal attribution groups. Path coefficients for the mediated model in each attribution group are presented in Table 5. CRd were calculated to determine which paths differed significantly between groups. The paths from social comparison to depression (CRd = 19.00, P < 0.05) and social comparison to anxiety (CRd = 5.40, P < 0.05) had CRd exceeding 1.96, indicating that these relationships were significantly stronger for adolescents with an internal attributional style than for those with an external style. For the internal attribution group, increased levels of social comparison were associated with greater symptoms of depression (β = 0.19, P < 0.001) and anxiety (β = 0.27, P < 0.001). In contrast, social comparison was not a significant predictor of depression (β = 0.01, P = 0.97) or anxiety (β = 0.05, P = 0.43) for the external attribution group.
β, standardised coefficient; CRd, critical ratio of difference.
*P < 0.05.
Mediation model effect decomposition
To further explore the nature of relationships within the mediation model for each attribution group, effect decomposition was conducted (Fig. 1). Standardised direct, indirect and total effects of self-acceptance on depression and anxiety were estimated separately for external and internal attribution groups. In the external attribution group, for depression, the direct effect of self-acceptance was −0.56 (95% CI −0.70 to −0.42), indicating that lower self-acceptance significantly predicted higher depression. The indirect effect via social comparison was 0.001 (95% CI −0.04 to 0.04) and did not contribute significantly to the total effect. The total effect of self-acceptance on depression was −0.56 (95% CI −0.70 to −0.42). The same results held for anxiety, with a significant direct effect of self-acceptance on anxiety and a non-significant indirect effect via social comparison. For adolescents who have an external attributional style, the social comparison did not significantly influence the relationship between self-acceptance and symptoms of depression or anxiety. In the internal attribution group, both the direct effect of self-acceptance on anxiety and depression and the indirect effect through social comparison were significant.
Discussion
The aim of our study was to investigate the connections among self-acceptance, social comparison and mental health outcomes (anxiety and depression) in adolescents. In addition, we aimed to assess the potential mediating role of social comparison and to understand how attributional styles may influence these relationships. Our results uncovered significant findings that have further enriched our understanding of these relationships. First, we found that lower self-acceptance was associated with a higher propensity for social comparison, which in turn was associated with more severe symptoms of anxiety and depression. Our mediation model analysis also suggests that social comparison is a mediating factor between self-acceptance and these poor mental health outcomes. Second, our findings revealed a key role of attributional styles in these associations. Specifically, individuals with external attributional tendencies reported significantly higher depression and anxiety than those with internal tendencies. This new insight regarding the influence of attributional styles on mental health outcomes and their interaction with self-acceptance and social comparison substantially expands on existing knowledge in the field.
Interpretation of our findings and comparison with existing literature
Our initial crucial discovery indicated that adolescents exhibiting external attributional tendencies reported significantly higher levels of depression and anxiety compared with those with internal tendencies. This discovery resonates with the existing body of research in the field of attributional theory. For instance, Peterson & Seligman'sReference Peterson and Seligman18 groundbreaking work proposed that individuals with an external locus of control, often characterised by a belief that events in their lives are primarily influenced by external circumstances rather than their own actions, tend to exhibit higher rates of depression and anxiety. Our study provides further evidence supporting this theory, substantiating the concept that external attributional tendencies can be a significant predictor of mental health outcomes. Notably, the direct comparison between external and internal attributional styles in relation to anxiety and depression symptoms as demonstrated in our study adds a more nuanced understanding of this relationship and fills a gap in the literature.
The second central observation of our study was that lower levels of self-acceptance were associated with heightened tendencies for social comparison, which in turn were linked with increased symptoms of anxiety and depression. This finding broadens our understanding from the previous research focusing on the individual roles of self-acceptance and social comparison in mental health. A study conducted by Gilbert et alReference Gilbert, McEwan, Mitra, Franks, Richter and Rockliff35 indicated that self-acceptance is inversely related to depressive symptoms. Meanwhile, separate research by Gibbons & BuunkReference Gibbons and Buunk14 confirmed that individuals with higher tendencies for social comparison often report elevated levels of anxiety and depression. By intertwining these two factors, our study contributes to the field by highlighting the combined influence of self-acceptance and social comparison on mental health outcomes. Such a significant relationship is of particular relevance during adolescence. This is a stage marked by an increased importance of peer relationships and social acceptance, and thus higher social comparison tendencies.Reference Steinberg and Morris36 Lower self-acceptance may therefore be particularly harmful in this context, exacerbating social comparison and leading to increased symptoms of anxiety and depression.
Perhaps one of the most remarkable discoveries of our research was that social comparison did not have a major mediating effect on the association between self-acceptance and depression or anxiety in individuals with an external attributional style. This observation diverges from conventional wisdom of social psychology that posits social comparison as a universal process affecting mental health, regardless of attributional style.Reference Festinger11,Reference Gilbert, Price and Allan37 A few theories offer potential insight. First, attributional styles could shape cognitive appraisals, thus influencing emotional and behavioural outcomes tied to self-acceptance and social comparison. For instance, adolescents with an external attributional style may perceive adverse social comparisons as outcomes beyond their control, thereby mitigating the impact of social comparison on their mental well-being.Reference Peterson and Seligman18 Second, learned helplessness theoryReference Seligman and Beagley38 posits that individuals with an external attributional style may develop a sense of helplessness, which could lessen the emotional toll of unfavourable social comparisons. Finally, self-determination theoryReference Deci and Ryan39 proposes that the intrinsic versus extrinsic motivations governed by attributional styles might differently modulate how adolescents process self-acceptance and social comparison, thus leading to varied mental health outcomes.
Implications and future research
Although our study has laid groundwork in illustrating the moderating role of attributional styles, further research is needed to empirically test these potential mechanisms. Our findings indicate that the connection between self-acceptance, social comparison and mental health outcomes may be more complex than previously thought, involving moderating factors such as attributional styles. This finding may have more implications for adolescents, because adolescence is a critical period for the development of stable attributional styles,Reference Hankin, Abramson and Siler40 suggesting that interventions aimed at promoting healthier attributional styles during this period may be particularly beneficial. Furthermore, the role of attributional styles in our study resonates with the research that adolescence is a formative period for the crystallisation of attributional tendencies. This developmentally relevant angle is underscored by the emergent importance of peer comparison during adolescence.Reference Steinberg and Morris36 Therefore, our study not only adds a nuanced layer to our understanding of self-acceptance and social comparison as independent variables but also enriches the broader discourse on psychosocial development during adolescence. This suggests that targeted interventions aimed at fostering healthier attributional styles and coping mechanisms related to self-acceptance and social comparison may be particularly effective during this developmental phase.
However, our study also had some findings that were not entirely conclusive, leaving room for further investigation. For instance, although our findings indicate that social comparison has a varying influence depending on attributional style, the specific mechanisms of this effect remain elusive. Therefore, future research could delve into this area, examining the potential underlying psychological or neurobiological factors that could explain this interaction. Another potential area for future research would be to explore the role of other individual differences, such as personality traits or resilience factors, in the relationships between self-acceptance, social comparison and mental health outcomes.
Limitations
This study is subject to certain limitations. The cross-sectional design limits the ability to infer causality or directionality among the variables under study. A longitudinal approach would offer a more nuanced understanding of the temporal relationships between self-acceptance, social comparison, attributional style and mental health outcomes. Second, the data were collected using self-report measures, which are susceptible to biases, including social desirability. Future research could integrate alternative assessment methods, such as clinician evaluations or peer ratings, to triangulate the findings. Third, the sample is culturally specific, consisting solely of Chinese adolescents from clinical settings. This limits the generalisability of the findings to other cultural and demographic groups. Fourth, the use of convenience sampling from a clinical population narrows the scope of the study and may not fully represent the broader adolescent population. The application of these findings to community samples or other settings warrants caution. Consequently, future research should aim to replicate these findings in more diverse populations and settings to enhance external validity.
Data availability
The data-set analysed in the current study is available at https://1drv.ms/f/s!Ah0WQ_R767kBj1WjEICiSpYM5fzm?e=aJboEf.
Author contributions
Q.-N.R. and G.-H.S. contributed equally to the work. W.-J.Y. and G.-H.S. conceived and designed the experiments. Q.-N.R. performed the experiments. G.-H.S. conducted the data analysis. Q.-N.R., G.-H.S., J.-S.Y. and W.-J.Y. wrote and revised the manuscript. All authors approved the submitted version.
Funding
This work was supported by the Wenzhou Municipal Science and Technology Bureau (grant no. Y20210112, G20210027) and Zhejiang Medical and Health Science and Technology Project (grant no. 2023RC273).
Declaration of interest
None.
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