Subjects
This study enrolled 1454 South Korean children under age 6 years residing
in Dong-gu, Ulsan using stratified cluster sampling according to the area of
residence and the type/size of housing. From these, authors obtained data
from 1214 child-parent dyads, including 1- to 5-year-old children (610 boys
and 604 girls) and their parents (278 fathers and 936 mothers) via dental
examination and self-administered questionnaire in July 2006.