Twenty four schools were selected for the
project: 12 intervention and 12 control schools.
The 12 schools that made up the intervention
group were randomly sampled from the 60 primary
schools in Wellington City, stratified for
size and socioeconomic status (SES), using
Epi-Info RAN.19 A further two were sampled to
allow for up to two refusals. There was only one
refusal from the initial selection and the first of
the two replacement schools selected agreed to
take part. Twelve control schools were selected
by taking the schools nearest to the intervention
schools in size and SES. There was one
refusal from a control school. This school was
replaced with the next nearest in size and SES
from remaining schools who had not been
approached.
Written consent was obtained from all
schools before the project began and schools
were told whether they would be part of the
control group (receiving information alone) or
the intervention group (receiving the full health
promotion programme).