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
The 12 schools that made up the interventiongroup were randomly sampled from the 60 primaryschools in Wellington City, stratified forsize and socioeconomic status (SES), usingEpi-Info RAN.19