Designing effective digital behaviour interventions

• Main Author: Nguyen, Hien
• Published: University of Aberdeen 2011
• Subjects: 300.285
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542650

Digital behaviour interventions are information systems that deliver advice and support to help people change their attitudes and/or behaviours. This thesis investigated the design principles that can make digital behaviour interventions more effective. In particular, this thesis focused on the design of dialogue systems aimed to encourage healthy behaviours. First, we explored the collected empirical evidence of past successful digital interventions to identify the best practices in designing such interventions. Based on these principles, we proposed a novel framework for creating personalised digital behaviour interventions. The framework emphasizes the process of personalisation at three levels: (1) modelling a personalised, dynamic model of behaviour of each user, (2) employing a personalised set of behaviour change strategies, and (3) personalising the delivery of each strategy to each user. Next, we looked at the effectiveness of a number of tactics that can be used by a system to enhance the delivery of behaviour change strategies. First, we investigated the conflicting results reported on the effect of onscreen characters on the system’s credibility. An onscreen character can enhance the system’s credibility if its appearance portrays high credibility with respect to the topic discussed by the system. For each topic, people do have a preference for which they would like to learn from. Finally, we combined all our findings to implement MARY, a virtual health trainer that encourages regular walking. MARY delivers a personalised intervention by supporting personalised goal setting, providing personalised daily feedback and emotional support. A longitudinal acceptability and feasibility evaluation of MARY with twenty-five participants confirmed our separate findings in a realistic setting. 90% of the participants improved or maintained their attitude towards walking, 81% of the participants intended to walk more, and 67% of the participants increased their daily step count.