Twenty-eight studies were included (12,703 patients; range 42 to 4,246). Most studies were randomised; one was quasi-randomised, one was partly randomised, and one was a prospective cohort study. Five studies used allocation concealment, and none of them blinded outcome assessors. Participant drop-out ranged from 2.1% to 47.9%. Eighteen studies had subjective outcome measures only. The maximum follow-up was one year.
Nine RCTs reported that video interventions resulted in at least one significant behaviour change, including breast self-examination (one RCT), prostate cancer screening (one RCT), sunscreen adherence (one RCT), self-care adherence in patients with heart failure (one RCT), HIV testing (three RCTs), treatment compliance (one RCT), and female condom use (one RCT). The remaining 19 studies found no significant differences in behaviour change between intervention and control.