Effectiveness of a Smartphone application and wearable device for weight loss in overweight or obese primary care patients: protocol for a randomised controlled trial.

BACKGROUND: To evaluate the effectiveness of an experimental intervention based on standard diet recommendations plus free Smartphone application (app) and wearable device for weight loss, compared with the standard diet intervention alone, in primary care patients aged 18 years or older who are overweight or obese. METHODS/DESIGN: Multicentre randomized, controlled clinical trial. LOCATION: Primary health care centres in the city of Tarragona and surrounding areas. SUBJECTS: 70 primary care patients, aged 18 years or older, with body mass index of 25 g/m2 or greater who wish to lose weight. Description of the intervention: 12 months of standard diet recommendations without (n = 35) or with (n = 35) assistance of a free Smartphone app that allows the participant to maintain a record of dietary intake and a bracelet monitor that records physical activity. The outcomes will be weight loss at 12 months (primary outcome), changes in physical activity and cardiometabolic risk factors, frequency of app use, and participant satisfaction after 12 months. DISCUSSION: The results of our study will offer evidence of the effectiveness of an intervention using one of the most popular free apps and wearable devices in achieving weight loss among patients who are overweight or obese. If these new technologies are proven effective in our population, they could be readily incorporated into primary care interventions promoting healthy weight. The open design and study characteristics make it impossible for the participants and researchers to be blinded to study group assignment. Researchers responsible for data analysis will be blinded to participant allocation. TRIAL REGISTRATION: Clinical Register: NCT02417623. Registered 26 March 2015.