The Outcomes of Thirsty? Choose Water! A Randomised Controlled Trial to Determine The Effects of A Behavioural and an Environmental Intervention on Water and Sugar Sweetened Beverage Consumption in Adolescents.

Abstract

Background: Childhood obesity is a serious public health challenge in Australia, with approximately one in four (24.9%) children aged 5-17 years being overweight or obese. Sugar sweetened beverages are one contributing factor and detrimental to health. Adolescents are the highest consumers of these, with nearly 25% of NSW children aged 12-17 years consuming sugar sweetened beverages at least 5 or more times per week. This study aims to address this by encouraging adolescents to choose water instead of sugar sweetened beverages and determine the effectiveness of two interventions (one behavioural and one environmental) alone or combined in achieving this outcome.Methods: An open-label randomised controlled trial utilising a two-by-two factorial design recruited 61 schools from across three Local Health Districts in NSW, Australia, randomising them to one of four study arms: a behavioural intervention, an environmental intervention, both or neither. Student surveys, school level surveys and water flow measurement data was collected. The primary outcome was increased water consumption, with secondary outcomes including changes in SSB consumption. To quantify the individual and joint effects of the interventions on the consumption of water and SSBs, random effects multivariable ordinal logistic regression models were derived for each outcome.Results: For students receiving at least one intervention there was an increased odds (though not statistically significant) of higher water consumption compared to those that received no intervention; whilst there was a statistically significant decrease in SSB consumption for students who received both interventions combined (OR = .67; 95% confidence interval, 0.55-.082; P<0.01).Conclusions: Evidence regarding school based obesity prevention continues to emerge, however, to our knowledge this is the first Australian study focussed on examining effective school-based interventions to specifically promote the consumption of water and decrease the consumption of SSBs in adolescents. The combination of a behavioural and an environmental intervention had a greater effect on decreasing SSB consumption. This is noteworthy given SSBs are a key contributor to overweight and obesity. The delivery of these combined interventions in schools can add value to existing interventions that address the complex public health issue of overweight and obesity.Trial Registration: Australian and New Zealand Clinical Trials Register ACTRN12618000526279 10 April 2018 http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12618000526279