As children develop physiologically and emotionally, it is useful to define certain age-based groups. The following terminology is used in this section:

• Neonate (newborn): Birth to 1 mo
• Infant: 1 mo to 1 yr
• Young child: 1 yr through 4 yr
• Older child: 5 yr through 10 yr
• Adolescent: 11 yr through 17 to 19 yr

This section covers diseases and disorders unique to children (including those that may persist into adulthood) and those that have defining features different from adults. Pediatric diseases and disorders that are also prevalent in adults and manifest similarly (eg, pharyngitis, asthma, diabetes) are covered more fully elsewhere in The Manual.

Last full review/revision February 2010