When social problems erupt, one classic response of governments and organizations is to wade in with an information campaign. From automobile seat belts to AIDS to recycling, policy-makers wage war on our inappropriate behaviors with newspaper stories, brochures, and public service announcements.
The goals are often noble ones, the dollars spent gargantuan, and the outcomes all too predictable: Messages seem to change the behaviors of some people some of the time but have almost no discernible impact on most people most of the time (McGuire, 1986; Hornik, 1989).
The situation has so discouraged policy-makers in the past that the pattern was given its own, dismal label: minimal effects (for perhaps the earliest articulation of this name, see Lazarsfeld, Berelson, and Gaudet, 1944). If media messages have no impact, policy-makers opined, why bother?
Today's communication scholars would agree with yesterday's policy-makers that media messages are often poor catalysts for behavior change, but many would disagree with that “minimal effects” label. Mediated messages can have pronounced effects, they would suggest, just not the ones envisioned by those who design them.
As countries around the globe face the prospect of encouraging massive behavior changes in order to try to prevent or, at the least, cope with climate change, it will be tempting to resort to information campaigns. I would urge us to succumb to that temptation; after all, media campaigns offer dramatic economies of scale by reaching large audiences at relatively low cost with potentially useful information.