Pediatric Age Range Definition
The pediatric age range is birth through 18 years of age, encompassing infants (0-1 year), children (2-12 years), and adolescents (13-18 years). 1
Standard Age Categories
The American Academy of Pediatrics provides clear age-based definitions for pediatric populations:
The upper limit of pediatric care is 18 years, though this should not be rigidly enforced. 2 Multiple clinical practice guidelines consistently use this framework, including those for ADHD (age 4 years to 18th birthday) 3, 22q11.2 deletion syndrome (birth to 18 years) 3, and pediatric acute lymphoblastic leukemia (patients ≤18 years) 3.
Important Variations and Nuances
Neonatal Period
- Neonates are specifically defined as infants from birth to 28 days corrected for gestational age 3
- This distinction is critical for antithrombotic therapy and other specialized treatments where neonates require separate protocols from older infants 3
Preschool-Aged Children
- The term "preschool-aged" refers to children from age 4 years to the sixth birthday 3
- This subgroup receives special consideration in ADHD guidelines and other developmental assessments 3
Adolescent and Young Adult (AYA) Populations
- AYA patients may extend beyond age 18 in certain oncology settings, potentially including patients up to age 30 years when treated in pediatric oncology centers 3
- Adolescent medicine clinicians may continue care until age 21, recognizing that developmental maturity extends beyond the traditional 18-year cutoff 1
- The World Health Organization defines adolescents as 10 to 19 years of age, which differs from the AAP definition 1
Respiratory Scoring Rules
- Pediatric respiratory scoring rules can be used for children <18 years, with the option of using adult criteria for children ≥13 years 3
- Individual sleep specialists may choose to score children ≥13 years using adult criteria, though pediatric rules remain appropriate through age 18 3
Critical Clinical Considerations
Arbitrary age limits should be discouraged in clinical practice. 2 The decision to continue care with a pediatrician or transition to adult care should be made solely by the patient (and family, when appropriate) and the physician, taking into account:
- Physical and psychosocial needs of the patient 2
- Abilities of the pediatric provider to meet these needs 2
- Individual developmental maturity, which varies significantly between individuals of the same chronological age 1
- Presence of chronic diseases, which may delay autonomy development compared to peers 1
Transition Planning
Transition to adult care typically occurs between ages 16-21 years, depending on local jurisdiction and individual circumstances. 3 Despite being arbitrarily considered adults at age 18 years, many individuals require significant parental/caregiver support at transition, including for healthcare, education, and other life decisions 3.
Common Pitfalls to Avoid
- Avoid using overlapping age ranges (such as 0-4 years and 4-18 years) that create ambiguity about which guideline applies to children at boundary ages 1
- Do not use vague terms like "school-aged children" or "pre-pubertal" without specific age ranges, as these lack the clarity needed for clinical decision-making 1
- Do not establish rigid upper age limits based solely on chronological age without considering individual patient factors 2
- Recognize that young adults (18-25 years) are sparsely represented in most adult data and may require special consideration 3