Long-term Effectiveness of a Multistrategy Behavioral Intervention to Increase the Nutritional Quality of Primary School Students’ Online Lunch Orders: 18-Month Follow-up of the Click & Crunch Cluster Randomized Controlled Trial

<jats:sec> <jats:title>Background</jats:title> <jats:p>School food services, including cafeterias and canteens, are an ideal setting in which to improve child nutrition. Online canteen ordering systems are increasingly common and provide unique opportunities to deliver choice architecture strategies to nudge users to select healthier items. Despite evidence of short-term effectiveness, there is little evidence regarding the long-term effectiveness of choice architecture interventions, particularly those delivered online.</jats:p> </jats:sec> <jats:sec> <jats:title>Objective</jats:title> <jats:p>This study determined the long-term effectiveness of a multistrategy behavioral intervention (Click & Crunch) embedded within an existing online school lunch-ordering system on the energy, saturated fat, sugar, and sodium content of primary school students’ lunch orders 18 months after baseline.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>This cluster randomized controlled trial (RCT) involved a cohort of 2207 students (aged 5-12 years) from 17 schools in New South Wales, Australia. Schools were randomized to receive either a multistrategy behavioral intervention or the control (usual online ordering only). The intervention strategies ran continuously for 14-16.5 months until the end of follow-up data collection. Trial primary outcomes (ie, mean total energy, saturated fat, sugar and sodium content of student online lunch orders) and secondary outcomes (ie, the proportion of online lunch order items that were categorized as everyday, occasional, and caution) were assessed over an 8-week period at baseline and 18-month follow-up.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>In all, 16 schools (94%) participated in the 18-month follow-up. Over time, from baseline to follow-up, relative to control orders, intervention orders had significantly lower energy (–74.1 kJ; 95% CI [–124.7, –23.4]; P=.006) and saturated fat (–0