Figure 1.

Subject selection and follow-up. One hundred and thirty-six infants were admitted to St. Louis Children's Hospital born between gestational ages ≥23 to ≤30 weeks. Twenty-nine infants did not undergo MRI scan at term equivalent; 20 died, 7 withdrew, 1 transferred, and 1 parent refused the MRI. One hundred and seven infants underwent MRI at term equivalent and completed neurobehavioral testing. Twenty infants did not undergo 2-year developmental assessment; 12 were not able to be contacted, 4 were non-compliant, 2 died, and 2 withdrew. Eighty-seven infants underwent 2-year development assessment. Nine infants did not undergo 5-year developmental assessment; 4 were not able to be contacted, 4 were non-compliant, and 1 withdrew. Six infants re-engaged at the 5-year assessment; 4 were previously not able to be contacted and 2 were previously non-compliant. Eighty-four infants were evaluated at 5 years for developmental assessment.