Four-year Behavioural, Health Related Quality of Life and BMI Outcomes From a Cluster Randomized Whole of Systems Trial of Prevention Strategies for Childhood Obesity (Whostops Childhood Obesity)

Objectives: To test the effectiveness of the Whole of Systems Trial of Prevention Strategies for Childhood Obesity (WHOSTOPS) for behavioural, health related quality of life and Body Mass Index (BMI) outcomes.Design :Cluster randomized trial of ten communities randomly allocated (1:1) to start intervention in 2015(step one) or in 2019 (after 4-years).Setting:Community based trial in South West Victoria, Australia, including all major health and local council agencies.Participants: Data were collected from 59 participating primary schools April-June of 2015 (73% school participation rate); 2017 (69%), and 2019 (63%). Student participation rates were 80% in 2015 (1,792/2,516 invited), 81% in 2017 (2,411/2,963), and 79% in 2019 (2,177/2,720).Interventions: Local leaders, organisations and community members developed obesity prevention interventions and implementation measures using a five phase process to change existing conditions that lead to childhood obesity.Main outcome measures: Measured height and weight (Grades two, four and six), self-reported behavioural, and health-related quality of life (Grade four and six).Results: There was an intervention by time interaction in both age and sex standardizedBMI (BMIz) (p=0.031)and obesity/overweight prevalence (p=0.006). The control communities remained unchanged whereas BMIz and overweight/obesity prevalence decreased between 2015 and 2017 and increased between 2017 and 2019 in intervention communities. The intervention reduced take away food consumption (p=0.006) and improved physical (p=0.036) and global (p=0.036) health related quality of life. Water consumption increased among girls (p=0.019)as did energy-dense and nutrient poor snack consumption (p=0.015) and take-away food consumption among boys (p= 0.012). BMIz of the grade two cohort steadily increased.Conclusions: WHOSTOPS had a positive impact on takeaway food intake and health-related quality of life.Trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR): 12616000980437.Registered 26 July 2016 - Retrospectively registered https://www.anzctr.org.au/Trial/Registration/