Subjects
Subjects in this study were full-time secondary
school teachers in Hong Kong. There were no
exclusion criteria for this study. Thirty secondary
schools in different regions of Hong Kong were
chosen from amaster list of all the secondary schools
in Hong Kong. The authors initially contacted the
target schools’ principals by fax, telephone or a
direct visit to ask for their consent to take part in the
study. Those who refused to join were replaced by
another school. When the principal agreed to take
part in the study, questionnaires were delivered to
all the teachers in that school by hand. They were
collected from the school 1–3 weeks later.