Development of cognitive behavioral therapy based weight control mobile "BI'KILO" application and testing its effectiveness

mHealth applications can facilitate overcoming barriers in access to treatment, such as distance, stigmatization, and difficulties in accessing specialists, and provide cost-effectiveness. It is important to evaluate many psychological aspects of overweight and obesity, which are associated with increased morbidity and mortality rates, and associated areas in treatment. This study aims to test the effectiveness of the mobile weight control application Bi'Kilo in 4 main areas related to obesity. This study was supported by TÜBİTAK 1001- Scientific and Technological Research Projects Support Program with project number 122S049. 77 adults were randomized into the study group, which had access to all content of the Bi'Kilo mobile application, and the control group, which had access to only psychoeducation content. Anthropometric measurements were made, leptin, ghrelin and HOMA-IR values were measured, scales measuring eating attitudes and behaviors and five neurocognitive tests were applied to the participants. 33 participants completed the study. Our study found that using the Bi'Kilo mobile application decreased body mass index, weight, and emotional eating behavior and increased mindful eating and awareness behavior in the study group. Bi'Kilo mobile application developed at the end of the study is the first mobile application developed in Turkish, based on CBT; its effectiveness was evaluated with a randomized controlled study. In future studies, using guided application design in mHealth applications, increasing personalization and motivation components, evaluating food addiction separately, increasing physical activity content, defining user profiles and creating content specific to these profiles may increase the effectiveness. Key Words: weight control, mobile health, cognitive behavioral therapy, obesity