TABLE 1

Characteristics of the Preterm Cohort at Each Assessment From 3 to 12 Years of Age (N = 355)

3 y4.5 y6 y8 y12 y
N317313313321314
Attrition rate, %a1819191718
Child characteristics
    Gestational age, mean ± SD, wk28 ± 228 ± 228 ± 228 ± 228 ± 2
    Birth weight, mean ± SD, g963 ± 174966 ± 177965 ± 174967 ± 175965 ± 175
    Male gender, %5455535455
    Maternal steroid treatment, %3536363536
    Indomethacin use, %5051505050
    Severe brain injury, %66776
    BPD, %4545434345
Maternal factors
    Maternal education, %
        Less than high school1413141313
        High school4848475048
        >1 y of college3839393739
    Race/ethnicity, %b
        White non-Hispanic7373747272
        Black1919181919
        White Hispanic65677
        Other22322
Age at assessment, mean ± SD, y3.2 ± 0.14.7 ± 0.16.3 ± 0.28.3 ± 0.212.2 ± 0.4
  • a The attrition rate was calculated with a denominator of 385 eligible subjects for each assessment.

  • b The sum of percentages does not always equal 100% because of rounding.