Procedure
Teaching staff were given a Developmental
Behavior Checklist for each child in their classroom,
and 38 questionnaires were returned. Parent
questionnaires were mailed to each child's
home address by the school and then returned in
a prepaid envelope to the researchers. The response
rates (50% for fathers and 65% for mothers)
were within the typical range for survey research
of this sort. No postal reminders were issued
to parents because of two linked ethical issues:
(a) the researchers did not have access to the
parent database at the school for data-protection
reasons, and (b) parents were assured that their
response to the survey would not be made known
to the school. No data were available on nonresponders,
although the demographic data appear
to be reasonably representative of the parents
whose children attend the school.