Dimensions of the severity of a health threat: the persuasive effects of visibility, time of onset, and rate of onset on young women's intentions to prevent osteoporosis.

Examined the persuasive effects of information about different aspects of the severity of a health threat. The research participants were 170 young women who were at risk for osteoporosis because they neither consumed an adequate amount of calcium daily nor performed an adequate amount of weight-bearing exercise. A message describing osteoporosis as disfiguring and highly visible increased beliefs in its severity and strengthened intentions to adopt the communicator's recommended preventive responses. In addition, compared with control conditions, describing the threat as likely to occur in the near future, as opposed to the distant future, also strengthened intentions. Furthermore, motivation to prevent osteoporosis remained high regardless of whether subjects believed it might occur to them in the near or distant future if they believed it was highly visible or disfiguring. The rate of onset (sudden or gradual) had no effect on intentions. Several implications for preventive health psychology are discussed. First, health promotion campaigns should, whenever possible, emphasize the immediate onset of a health threat and any visible features. Second, in order to convince people a health threat can be severe, the sudden rate of onset should be emphasized whenever possible.