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In 2002/2005, separate energy requirement equations were generated by the Institute of Medicine's (IOM) Dietary Reference Intake process for normal weight and overweight/obese children and adolescents. The current paper questions the theoretical rationale of having two sets of equations (based solely on body-weight classification): when body weight is considered, overweight and obese children and adolescents do not seem to differ from their normal weight counterparts in energy expended for basal metabolism or physical activity tasks. However, energy needs for weight maintenance among overweight/obese girls were consistently higher when predicted using the equations for overweight/obese individuals compared with those developed for normal weight individuals. In contrast, among overweight/obese boys, they were consistently lower . Although the differences are within the variability of the estimates, even theoretical support for a higher energy intake (as occurs in girls) seems unwise because of the potential contribution to a higher body mass in children who are already at risk. It is the opinion of the authors that the IOM revisit the use of two separate equations and generate one set that is appropriate for all children and adolescents. 相似文献
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Rebecca P. Ang Robert M. Klassen Wan Har Chong Vivien S. Huan Isabella Y.F. Wong Lay See Yeo Lindsey L. Krawchuk 《Journal of adolescence》2009,32(5):1225-1237
We provide further evidence for the two-factor structure of the 9-item Academic Expectations Stress Inventory (AESI) using confirmatory factor analysis on a sample of 289 Canadian adolescents and 310 Singaporean adolescents. Examination of measurement invariance tests the assumption that the model underlying a set of scores is directly comparable across groups. This study also examined the cross-cultural validity of the AESI using multigroup confirmatory factor analysis across both the Canadian and Singaporean adolescent samples. The results suggested cross-cultural invariance of form, factor loadings, and factor variances and covariances of the AESI across both samples. Evidence of AESI's convergent and discriminant validity was also reported. Findings from t-tests revealed that Singaporean adolescents reported a significantly higher level of academic stress arising from self expectations, other expectations, and overall academic stress, compared to Canadian adolescents. Also, a larger cross-cultural effect was associated with academic stress arising from other expectations compared with academic stress arising from self expectations. 相似文献