Our Methodology: Inside the 2012-13 Best Children's Hospitals Rankings

Seriously sick kids need expertise that can't be found at most hospitals, where all but a few inpatients are adults. Children, as a popular medical school saying goes, aren't small adults. They are more vulnerable to infections because their immune systems aren't fully developed. They respond to medications faster and are more sensitive to too high or too low a dose. Their treatment may be much different than for an adult with the same condition. Moreover, kids are smaller; operating on walnut-sized hearts and starting IVs in veins that make spaghetti look big are only two of the challenges that pediatric specialists face day in and day out.