Cluster randomised controlled trial of an online intervention to improve healthy food purchases from primary school canteens: a study protocol of the ‘click & crunch’ trial

- Wyse, Rebecca; Delaney, Tessa; Attia, John; Oldmeadow, Chris; Sutherland, Rachel; Nathan, Nicole; Reilly, Kathryn; Reeves, Penny; Wolfenden, Luke; Gibbins, Pennie; Ball, Kylie; Campbell, Karen; Yoong, Sze Lin; Seward, Kirsty; Zoetemeyer, Rachel; Rissel, Chris; Wiggers, John