JultikaUniversity of Oulu repository

The purpose of this thesis is to study the process of designing and developing a web-based application for supporting people struggling with overweight to change their behaviour in order to prevent health risks. Obesity and its co-morbidities represent one of the major public health problems globally. To prevent health problems caused by overweight, such as the metabolic syndrome, a sustainable change in an individual’s health behavior is required. Behavior Change Support Systems (BCSSs) have been introduced as objects of study in the field of persuasive technology, defined as information systems designed to form, alter or reinforce attitudes, behaviors or an act of complying without using deception, coercion or inducements. One of the most prominent domain areas for these systems is promoting behavior change for improved health and healthier lifestyles. Despite the importance of the research domain, descriptions from the systems in most cases have been presented in too general level to be benefited from. In the scope of this thesis, we built a full-fledge BCSS within the weight loss and maintenance domain to support users lifestyle change process during a 52-week long intervention. The system design process is studied here to find re-usable conceptual designs such as software architectures and design patterns for future BCSS development and research.