BackgroundSocial connection factors play a key role for young people's mental health. It is important to understand how their influence may vary across contexts. We investigated structural (e.g. household size), functional (e.g. social support) and quality (e.g. feeling close) social connection factors in relation to adolescent internalising and externalising symptoms, comparing two countries Brazil and the United Kingdom (UK).MethodsWe pooled data from the UK Millennium Cohort Study (MCS) and the Brazilian High Risk Cohort Study (BHRCS). We included 12 social connection variables, identified through retrospective harmonisation and lived experience expert involvement. We tested measurement invariance and conducted multiple regressions to analyse associations between the social connection factors (age 14) and later internalising and externalising difficulties (age 17.5) in both cohorts. We investigated country‐level interactions and used weights to account for attrition, survey design, population representativeness and sample size.ResultsWe found pooled main associations with later internalising symptoms for ‘living with half‐siblings’ (p < .001), ‘moving address’ (p = .001), ‘mother marital status’ (p < .001–.003), ‘bullying’ (p = .001), ‘being bullied’ (p < .001) and ‘difficulties keeping friends’ (p < .001). For externalising, we found main associations with ‘household size’ (p = .041), ‘moving address’ (p = .041), ‘mother's marital status’ (p = .001–.013), ‘bullying others’ (p < .001) and ‘being bullied’ (p < .001). Country‐level interactions suggested higher internalising symptoms were associated with ‘household size’ (p = .001) in Brazil and ‘being bullied’ (p < .001) in MCS. Additionally, ‘half‐siblings in household’ (p = .003), ‘poor mother–child relationship’ (p = .018), ‘single mother’ (p = .035), ‘bullying’ (p < .001) and ‘being bullied’ (p < .001) were more strongly linked to externalising difficulties in MCS.ConclusionsSocial connection factors, mostly structural, contributed to adolescent internalising and externalising difficulties in both countries. Factors relating to bullying and family composition seem to play a stronger role in each country. Cultural and socioeconomic factors might explain these differences. Future research should investigate cross‐regional differences to meaningfully inform global mental health efforts.

中文翻译：

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社会联系及其与青少年内化和外化症状的预期关联：一项使用回顾性协调的探索性跨国研究


背景社会联系因素对年轻人的心理健康起着关键作用。了解它们的影响如何因环境而异非常重要。我们调查了与青少年内化和外化症状相关的结构性 （例如家庭规模）、功能 （例如社会支持） 和质量 （例如感觉亲密） 社会联系因素，比较了巴西和英国 （UK） 两个国家。方法我们汇总了来自英国千年队列研究 （MCS） 和巴西高风险队列研究 （BHRCS） 的数据。我们纳入了 12 个社会联系变量，这些变量是通过回顾性协调和生活经验专家参与确定的。我们测试了测量不变性并进行了多元回归，以分析两个队列中社会联系因素 （14 岁） 与后来的内化和外化困难 （17.5 岁） 之间的关联。我们调查了国家层面的互动，并使用权重来解释流失、调查设计、人群代表性和样本量。结果我们发现，与“与同父异母的兄弟姐妹同住”（p < .001）、“搬家”（p = .001）、“母亲婚姻状况”（p < .001–.003）、“欺凌”（p = .001）、“被欺负”（p < .001）和“难以保持朋友”（p < .001）等内化症状的主要关联。对于外化，我们发现与“家庭规模”（p = .041）、“搬家地址”（p = .041）、“母亲的婚姻状况”（p = .001–.013）、“欺负他人”（p < .001）和“被欺负”（p < .001）之间存在主要关联。国家层面的交互作用表明，较高的内化症状与巴西的“家庭规模”（p = .001）和 MCS 的“被欺凌”（p < .001）相关。此外，“家庭中同父异母的兄弟姐妹”（p = .003）、“母子关系差”（p = .018）、“单身母亲”（p = .035）、“欺凌”（p < .001）和“被欺负”（p < .001）与 MCS 的外化困难更密切相关。结论社会联系因素，主要是结构性因素，导致了这两个国家的青少年内化和外化困难。与欺凌和家庭构成相关的因素似乎在每个国家/地区都发挥着更重要的作用。文化和社会经济因素可能解释了这些差异。未来的研究应调查跨区域差异，以有意义地为全球心理健康工作提供信息。