A number of unique challenges may affect the child health research enterprise.9 In the developed world, the majority of children are healthy, limiting the pool of potential participants in research studies and underscoring the need for multicenter research networks. The types of diseases in children, including many behavioral and emotional conditions, may be challenging to study. Research in pediatrics needs to consider a child's age and developmental stage, which may require a larger study population and a longer time frame.10 Unlike studies in adults, studies in children are complicated by the necessary participation of the parent or caregiver. Children depend on adults to recognize their illness, take them for care, and make decisions about treatment, adding another layer of complexity in studying child health. In addition, parents or caregivers often provide information to researchers, rather than the data being obtained directly from the child-participant. In attention-deficit hyperactivity disorder, for example, ratings by parents and teachers are required.11 Parents must provide informed consent for their child's participation in a study, which can lower the participation rate.10 For example, parents may be reluctant to agree to research participation if a potentially painful procedure is involved. In addition, ethical considerations loom large when the research participant is a child. The amount of acceptable risk5 and whether financial incentives should be provided to parents of minors7 are 2 such issues. Finally, outcomes may be less immediate or harder to measure. For instance, reducing cardiovascular disease in adulthood by preventing obesity in a child is more difficult to measure than the rapid weight loss following gastric bypass surgery. How to translate short-term data from childhood into long-term outcomes over the lifespan is challenging.10