Studies were included if they focused on HIV/AIDS prevention interventions, were aimed at young people or the general public, and investigated a specific intervention delivered thorough audio, visual, or printed mass-media in a natural setting. Studies had to provide quantitative data comparing condom use and/or HIV/AIDS-related knowledge in the population pre- and post-intervention. Studies were included if they reported sufficient data to allow the calculation of effect sizes. Studies were excluded if they focused on high-risk populations, used forced exposure to messages, only included individuals who had all been exposed to some campaign content, or if they used interpersonal communication and small media (such as leaflets).
Just over half of the included studies were aimed at the general public, the rest targeted young people. The mean age of participants was 24.25 years. There were approximately equal numbers of men and women participants. The mean proportion of sexually active people was 69%. Most interventions were aimed at condom promotion/education; 42% of interventions included condom distribution. Radio and signage were the most frequently used media channels, with most interventions using a logo, slogan, or brand. Most studies used either a national or a community-based media campaign.
Study data were collected from 1986 to 2005. Half the studies were conducted in Africa. The remaining studies were set in Asia, Europe, the USA, South/Central America, and Australia.
Two authors independently screened papers for inclusion. Any disagreements were resolved in discussion.