Corrected age for preterm infants
Corrected (postconceptional) age for developmental assessment of preterm infants up to 24 months.
About this calculator
The corrected age of a preterm infant is the chronological age adjusted for gestational age, used to assess growth and developmental milestones. Applied up to 24 months per American Academy of Pediatrics (Pediatrics, 2004). Formula. Corrected age = chronological age – (40 weeks – gestational age at birth). Example: a baby born at 32 weeks who is 6 calendar months old – corrected age is 6 - 2 = 4 months. Where applied. Growth assessment on percentile curves (CDC, WHO). Neurodevelopmental milestones – motor, language, cognition. Vaccination and feeding follow chronological age, not corrected age. Thresholds. Below 28 weeks GA – correction up to 36 months (in early intervention programs). 28-32 weeks – up to 24 months. 33-37 weeks – up to 12 months. After these timelines the child catches up to peers. Clinical use. Differential diagnosis of developmental delay. In high-risk infants under 24 months (prematurity, IVH, BPD, asphyxia) assessment uses corrected age – otherwise delay is falsely diagnosed. After 24 months chronological age is used with standard screening tools (PEDS, ASQ-3, M-CHAT for autism).
Source
Formula version: aap-2004-2024-v1
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