The Effects of Salient Nudging in Technology-Based Interventions for Physical Activity: A Longitudinal Field Experiment
Dr Teo Hock Hai, Provost'S Chair Professor, School of Computing
ABSTRACT:
The promotion of physical activity to prevent obesity and non-communicable diseases is a well-established agenda for health state institutions. With recent advances in information and communication-based technologies, the use of 'technology-based interventions' for physical activity is becoming more ubiquitous. In response, a growing body of research has evaluated the association between the use of the interventions and physical activity behavior. However, recent literature reviews reported conflicting results on the interventions' effects on the behavior. A potential explanation is the context of intervention use or the paucity of research thereof. As the interventions become more sophisticated in design, new opportunities emerge to incorporate context into the interventions, such as using 'salient nudges' where parts of the interventions (i.e. features) are modified in subtle yet targeted ways that guide users' choices or influence their inputs. As these nudges have significant potential to change the way information is presented and guide users towards desirable thoughts, a systematic evaluation of salient nudging can provide useful insights on designing efficacious interventions.
In response, this thesis introduces and tests a framework on the effects of salient nudging in technology-based interventions for physical activity. Referencing self-determination and nudging theory, the framework proposes how access to different features of the intervention can be subtly modified via salient nudging to match an individual' s profiled motivations concerning physical activity. To test the framework, a prototype technology-based intervention based on the framework was developed to profile users and assign relevant salient nudges. The intervention was deployed in a longitudinal randomized controlled trial with two parallel study arms. Findings from the trial revealed a significant treatment effect of salient nudging on the likelihood of a user developing more intrinsic motivations to exercise. More specifically, salient nudging in the intervention was positively associated with higher probabilities of transitions to a more motivated state of physical activity regulation over time if the user was initially profiled before using the intervention to experience weak (i.e. extrinsic) or strong (i.e. intrinsic) self-determined motivation for physical activity.
Overall, the thesis calls for considering context when developing technology-based interventions for physical activity. This can be done by profiling the context of the users and configuring the display of information in the interventions using salient nudges to match the profiles. These initiatives can subsequently promote the likelihood for users, especially those who are initially weakly motivated, to develop more motivating thoughts.
This thesis concludes by discussing detailed results, implications, and suggestions for future research.