As with previous survey rounds, the questionnaire was
made available to secondary schools across North West
England through local authority Trading Standards departments
[15-17]. Within schools, the questionnaire
was delivered to students by teachers during normal
school lessons between January and April 2013. Students
self-completed the questionnaire voluntarily and anonymously.
Compliance was not recorded by schools
with the sample not intended to be representative of
North West school children, but rather to provide a
broad sample of students from a range of community
types. A total of 114 schools participated, with representation
from schools in all 23 upper tier local authorities
in the region. The initial survey in 2005 was approved
by the Trading Standards North West Executive Committee
and schools participate on a voluntary basis
under their own approval systems. Ethical approval to
analyse the survey data for this study was obtained from
Liverpool John Moores University Research Ethics
Committee.