The study has several limitations, according to the authors. Although the data are nationally representative, they are cross-sectional and don’t represent temporal changes at an individual level. The data are also insufficient to obtain a confident diagnosis of clinical disease and as a result may underestimate ideal levels of CV health components. Also, the Cardiovascular Health Score does not weight the influence of each individual component, "and should be interpreted in light of this limitation," the authors noted.
They also noted that it is important to consider the fluctuations in health factors – such as increases in total cholesterol levels – that occur naturally during puberty and adolescence. Since NHANES is a cross-section, it does not allow for serial evaluation of CV factors, which could as a result increase the likelihood of misclassification.
The study was supported in part by a grant from the National Heart, Lung, and Blood Institute. None of the authors reported any disclosures except for Dr. Stephen R. Daniels who was the chair of the Data Safety and Monitoring Board for Merck Pharmaceuticals.
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