Within the fields of e-health and persuasive technology, research indicates that intervention websites can motivate people to adopt healthy behaviours, such as quitting smoking, exercising more, and eating better. Frequently, these online interventions are individually tailored programmes, resembling two-way interpersonal therapy. It is now conceivable that health campaigners can deploy mass-interpersonal campaigns, where online media are used to engage large populations in automated personal relationships, similar to relationships people have with their doctors, councillors, trainers, and trusted friends.

This presentation provides some key findings from a meta-analysis investigating the psychological design factors that can explain the efficacy of online behavioural change interventions. It makes a clear distinction between mass-media, interpersonal and mixed, mass-interpersonal communications. To this end, a model, called ‘the Communication-Based Influence Components Model’, is used to synthesize behavioural change and persuasion taxonomies.

To assess the psychological design of online interventions, the meta-analysis synthesized 30 interventions, which included 17,524 study participants. The statistical results showed that online interventions, modelled on interpersonal interaction, work.