4 Traditionally, behavioural weight loss interventions recommend overweight or obese individuals increase physical activity, improve dietary quality and reduce energy intake to create an energy deficit of 2500 kilojoules per day. 3 For individuals who are overweight or obese, weight loss of >5% is associated with clinically significant reductions of risk of ill health.

1 2 Being overweight or obese increases the risk of developing coronary heart disease and type 2 diabetes mellitus.

Globally, the prevalence of overweight and obesity has increased between 19, and currently, in Australia, 63% of adults are overweight or obese. Generalised linear models using an analysis of covariance (baseline adjusted) approach will be used to identify between-group differences in primary and secondary outcomes, following an intention-to-treat principle. Participants will receive a Fitbit, body weight scales to facilitate self-monitoring, and use the app to access educational material, set goals, self-monitor and receive feedback about behaviours. The multicomponent m-Health intervention will be delivered using a smartphone/tablet ‘app’, supplemented with email and SMS and individualised in-person dietary counselling. Assessments will be conducted at baseline, 6 months (primary endpoint) and 12 months (follow-up). The secondary aims are to compare the relative efficacy of a physical activity, dietary behaviour and sleep intervention (enhanced intervention), compared with a physical activity and dietary behaviour only intervention (traditional intervention), on the primary outcome of weight loss and secondary outcomes of waist circumference, glycated haemoglobin, physical activity, diet quality and intake, sleep health, eating behaviours, depression, anxiety and stress and quality of life. The primary aim of this three-arm randomised controlled trial is to examine the efficacy of a multicomponent m-Health behaviour change weight loss intervention relative to a waitlist control group.

Measure Twice by J.J. Hensley