BackgroundResearchers and practitioners have developed numerous online interventions that encourage people to reduce their drinking, increase their exercise, and better manage their weight. Motivations to develop eHealth interventions may be driven by the Internet’s reach, interactivity, cost-effectiveness, and studies that show online interventions work. However, when designing online interventions suitable for public campaigns, there are few evidence-based guidelines, taxonomies are difficult to apply, many studies lack impact data, and prior meta-analyses are not applicable to large-scale public campaigns targeting voluntary behavioral change.ObjectivesThis meta-analysis assessed online intervention design features in order to inform the development of online campaigns, such as those employed by social marketers, that seek to encourage voluntary health behavior change. A further objective was to increase understanding of the relationships between intervention adherence, study adherence, and behavioral outcomes.MethodsDrawing on systematic review methods, a combination of 84 query terms were used in 5 bibliographic databases with additional gray literature searches. This resulted in 1271 abstracts and papers; 31 met the inclusion criteria. In total, 29 papers describing 30 interventions were included in the primary meta-analysis, with the 2 additional studies qualifying for the adherence analysis. Using a random effects model, the first analysis estimated the overall effect size, including groupings by control conditions and time factors. The second analysis assessed the impacts of psychological design features that were coded with taxonomies from evidence-based behavioral medicine, persuasive technology, and other behavioral influence fields. These separate systems were integrated into a coding framework model called the communication-based influence components model. Finally, the third analysis assessed the relationships between intervention adherence and behavioral outcomes.ResultsThe overall impact of online interventions across all studies was small but statistically significant (standardized mean difference effect size d = 0.19, 95% confidence interval [CI] = 0.11 - 0.28, P < .001, number of interventions k = 30). The largest impact with a moderate level of efficacy was exerted from online interventions when compared with waitlists and placebos (d = 0.28, 95% CI = 0.17 - 0.39, P < .001, k = 18), followed by comparison with lower-tech online interventions (d = 0.16, 95% CI = 0.00 - 0.32, P = .04, k = 8); no significant difference was found when compared with sophisticated print interventions (d = –0.11, 95% CI = –0.34 to 0.12, P = .35, k = 4), though online interventions offer a small effect with the advantage of lower costs and larger reach. Time proved to be a critical factor, with shorter interventions generally achieving larger impacts and greater adherence. For psychological design, most interventions drew from the transtheoretical approach and were goal orientated, deploying numerous influence compon...

This paper discusses problems faced by planners of real-world online behavioural change interventions who must select behavioural change frameworks from a variety of competing theories and taxonomies. As a solution, this paper examines approaches that isolate the components of behavioural influence and shows how these components can be placed within an adapted communication framework to aid the design and analysis of online behavioural change interventions. Finally, using this framework, a summary of behavioural change factors are presented from an analysis of 32 online interventions.

Abstract. This paper evaluates data from an international anti-poverty campaign to assess if common principles from e-marketing and persuasive technology apply to online social marketing. It focuses on the relationships between website credibility, users' active trust attitudes and behavioural intent. Using structural equation modelling, the evaluation found a significant relationship between these variables and suggests strategies for online behavioural change interventions.

Abstract:Having engaged one billion users by early 2006, the Internet is the world's fastest-growing mass communications medium. As it permeates into countless lives across the planet, it offers social campaigners an opportunity to deploy interactive interventions that encourage populations to adopt healthy living, environmental protection and community development behaviours. Using a classic set of social campaigning criteria, this paper explores relationships between social campaign websites and behavioural change.