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Key MessageAlthough obesity measures have been consistently associated with a lower FEV1/FVC ratio in adolescents, no previous study has assessed the underlying mechanisms of this association This population-based study assessed whether insulin resistance and CRP levels at 15 years partially mediate the association between fat mass and FEV1/FVC using a causal mediation analysis approach. The findings suggest that insulin resistance at 15 years may mediate over 20% of this association, but no evidence of a mediating role of CRP was found. Further, longitudinal studies that evaluate other biomarkers of systemic inflammation and examine other potential mechanisms are needed to better understand the pathways linking obesity and respiratory health in adolescence. This is key for public health interventions and targeting clinical interventions.AbstractBackgroundWe previously reported an association of high fat mass levels from age 9 to 15 years with lower forced expiratory flow in 1 s (FEV1)/forced vital capacity (FVC) ratio (i.e., increased risk of airflow limitation) at 15 years. Here, we aimed to assess whether insulin resistance and C-reactive protein (CRP) at 15 years partially mediate this association.MethodsWe included 2263 children from the UK Avon Longitudinal Study of Parents and Children population-based cohort (ALSPAC). Four fat mass index (FMI) trajectories (“low,” “medium-low,” “medium-high,” “high”) from 9 to 15 years were previously identified using Group-Based Trajectory Modeling. Data on CRP, glucose, insulin, and post-bronchodilator FEV1/FVC were available at 15 years. We defined insulin resistance by the homeostasis model assessment-estimated insulin resistance index (HOMA-IR). We used adjusted linear regression models and a causal mediation analysis to assess the mediating role of HOMA-IR and CRP.ResultsCompared to children in the “low” FMI trajectory, children in the “medium-high” and “high” FMI trajectories had lower FEV1/FVC at 15 years. The percentage of the total effect explained by HOMA-IR was 19.8% [−114.1 to 170.0] and 20.4% [1.6 to 69.0] for the “medium-high” and “high” trajectories, respectively. In contrast, there was little evidence for a mediating role of CRP.ConclusionThe association between mid-childhood fat mass and FEV1/FVC ratio at 15 years may be partially mediated by insulin resistance.

Dynamic Assessment has recently been voiced of constructivism, the socio-cultural theory of learning. This article, challenging the psychometric and product-based test, makes an attempt to delve into the epistemological and ontological theories of Dynamic Assessment (DA) and their criticisms. DA is the offspring of Vygotsky’s theory of the Zone of Proximal Development (ZPD) and Feuerstein’s mediated learning experience (MLE). It emphasises constructing a future through mediations. Interestingly, this development-oriented process of collaboration relies on the unification of instruction and assessment which is a strong threat to the reliability of the psychometric tests. This study also deals with the battle of views on DA. It discusses the appealing face of DA embracing ethical values, fairness and social equity, and the process based assessment. It also argues the negative face of DA comprising modifiability, interventionism, and stability. It finally concludes that each system should be criticised by certain criteria. Faced with the scarcity of research both theoretically and empirically, the critical analysis of this new generation of test in an L2 setting might be helpful for further discussions, suggestions and implications in the second language learning arena.