TABLE 1.

Demographic and Clinical Features of Childhood-Onset ET

VariableMale PatientsFemale PatientsP
Result%Result%
No.2974.41025.6.003
Age at onset, y9.2 ± 4.77.9 ± 5.7
Age at evaluation, y19.3 ± 12.923.4 ± 18.5
Positive family history (1°)22 (of 29)75.95 (of 10)50.0.23
Positive family history (>1°)16 (of 21)76.27 (of 8)87.5.65
  • 1° indicates first-degree relatives; >1°, second-degree or more distantly related relatives.