The instability hypothesis proposes that family structure transitions lead to negative child outcomes through the pathway of stress. However, in many cases, family structure transitions are not associated with stress or negative child outcomes, suggesting that there are specific circumstances under which transitions are more or less stressful. Using five rounds of data (ages 1-15) from the Young Lives study (N = 8,062) which follows children and their caregivers in Ethiopia, India, Peru, and Vietnam, we had two aims: (a) to test the instability hypothesis, and (b) to examine the specific circumstances under which family structure transitions lead to stress and worsened child physical health. First, we used multilevel mediation to assess whether financial stress mediated the link between family structure transitions and children's physical health. We then added household size, multigenerational household, and horizontally extended kin household as moderators to the family structure transition-financial stress relationship. We found that financial stress did not mediate the link between family structure transitions and children's physical health in any of the Young Lives countries. We found some moderated mediation effects for household size and multigenerational households in Peru and Vietnam, but effect sizes were small. These findings highlight the need to further unpack the instability hypothesis to understand the specific circumstances under which family structure transitions lead to stress and worsened child outcomes. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

中文翻译：

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对低收入和中等收入国家不稳定假说的检验。

不稳定假说认为，家庭结构转变通过压力途径导致负面的儿童结局。然而，在许多情况下，家庭结构的转变与压力或负面的儿童结局无关，这表明在某些特定情况下，家庭结构的转变或多或少会产生压力。使用来自 Young Lives 研究 (N = 8,062) 的五轮数据（1-15 岁），该研究跟踪埃塞俄比亚、印度、秘鲁和越南的儿童及其照顾者，我们有两个目标：(a) 检验不稳定假设，以及（b）研究家庭结构转变导致压力和儿童身体健康状况恶化的具体情况。首先，我们使用多层次中介来评估经济压力是否介导了家庭结构转变与儿童身体健康之间的联系。然后，我们添加了家庭规模、多代家庭和横向延伸的亲属家庭作为家庭结构转型-财务压力关系的调节因素。我们发现，在任何“年轻生命”国家中，经济压力并没有调节家庭结构转变与儿童身体健康之间的联系。我们发现秘鲁和越南的家庭规模和多代家庭的中介效应有所减弱，但效应规模很小。这些发现强调需要进一步解开不稳定假说，以了解家庭结构转变导致压力和儿童结局恶化的具体情况。（PsycInfo 数据库记录 (c) 2023 APA，保留所有权利）。