To the Editor: The cohort study by Dr Van Cleave and colleagues1 documented dynamics in the prevalence of chronic health conditions in US children between 1988 and 2006 using data from the National Longitudinal Survey of Youth–Child Cohort. The authors concluded that the prevalence of chronic conditions among children and youth increased significantly during this interval. However, it is not clear whether these increases are real or a function of what is classified by researchers or reported by parents as a chronic condition.
Kaczorowski J. Chronic Health Conditions and Obesity Among Children and Youth. JAMA. 2010;303(19):1915-1916. doi:10.1001/jama.2010.585