Testing innovative methods to improve the reach and effectiveness of web-based physical activity interventions

Insufficient levels of physical activity increase the risk of developing cardiovascular disease, some cancers, diabetes, osteoporosis, depression, anxiety and obesity. However, less than half of the Australian population meet the minimum physical activity guidelines of accumulating 30 minutes of moderate intensity physical activity on most days of the week. This increases the burden of disease, lowers quality of life and costs the health care system over AUD $719 million per year. Therefore, there is an urgent need for effective population based interventions to increase physical activity at low cost for large numbers of people. The Internet provides a good platform to deliver physical activity interventions as it can reach large numbers of people at low cost. Whilst the short-term effectiveness of web-based interventions has been established, effective promotion of web-based interventions, as well as long-term participant engagement and retention into web-based interventions, can be problematic and needs to be addressed in order to improve the long-term effectiveness of these kinds of interventions. Therefore, the first study examined the cost-effectiveness of web-based advertising methods compared to traditional print-based advertising methods, as they have the potential to attract large numbers of people into a web-based physical activity intervention at a lower cost. For the second study, a 3-group randomised controlled trial was conducted to determine the effectiveness (in terms of retention, adherence, website engagement, satisfaction, physical activity changes and quality of life changes) of using online video-coaching (using Skype) in addition to personally-tailored physical activity advice. For the third study the effectiveness of video-tailored advice to improve attention and recall of the physical activity message was compared to basic text-tailored advice using eyetracking technology and a recall questionnaire. Findings from the recruitment evaluation (study 1) revealed that the cost-effectiveness of both the web-based and print-based methods varied substantially. Newspaper articles and community calendars cost the least per sign-up, but resulted in a small number of sign-ups (17 and 6 respectively). The targeted Facebook advertisements were the next most cost-effective method (AUD $45 per sign up), and reached the most number of sign-ups (184). People reached through the targeted Facebook advertisements were on average older and had a higher BMI than people reached through the other methods. Google advertisements and newspaper advertisements were not cost effective. Further research is needed to determine the effectiveness of Facebook advertising for attracting specific population groups and evaluate the use of mass-media to attract larger numbers to population level interventions. The intervention trial (study 2) revealed that the tailored advice + video-coaching group significantly improved their physical activity in comparison to a wait-list control group. However due to a low adherence to the coaching sessions, the tailored advice + video-coaching group did not improve their physical activity more than the tailoring only group. Participants who participated in the video-coaching sessions were nonetheless satisfied and had higher program and website engagement. Further research using online video-coaching should investigate ways to improve coaching adherence. The eye-tracking study (study 3) demonstrated that video-tailored advice leads to improved user-engagement compared to text-tailored advice (i.e., video participants paid more attention and interacted with the website for longer). However no group differences in recall of the physical activity message were found. More research is needed to determine how recall of computer-tailored advice can be improved and whether video-tailored advice can lead to greater health behaviour change than text-tailored advice. In summary, the findings from this PhD add valuable knowledge to the literature about improving the promotion, engagement and effectiveness of web-based physical activity interventions, and inform the development of the next generation of interventions