TABLE 2

Demographic Summary of Autism Case and Matched Control Subjects

CharacteristicControl Subjects (N = 242)Case Subjects (N = 121)
Gender, n (%)
    Female58 (24)29 (24)
    Male184 (76)92 (76)
Year of birth
    Median19871987
    IQR1981–19911981–1991
    Range1963–19951963–1995
Age met autism research criteria, y
    Mean (SD)NA7.3 (4.8)
    MedianNA6.1
    IQRNA3.4–9.7
    RangeNA1.9–20.9
Age at last follow-up before age <21, y
    Mean (SD)17.4 (3.6)16.0 (5.2)
    Median18.718.2
    IQR15.0–20.413.4–20.2
    Range3.8–21.02.7–21.0
  • IQR indicates interquartile range (25th–75th percentiles); NA, not applicable.