Efficacy of informational letters on hepatitis B immunization rates in university students.

A randomized, controlled trial was conducted at a private university to determine whether students who received an informational letter (n = 366) would be more likely to receive a hepatitis B vaccination than students in a control group (n = 366). Surveys were conducted to determine the students' reasons for deciding to be vaccinated. Rates of hepatitis B immunization were significantly higher among students assigned to the intervention group (10.7%) than among the control group (1.9%). Vaccinated students were more likely than unvaccinated students to report having had 3 or more sexual partners in the past 6 months. Students at higher risk for hepatitis B infection were more likely than others to be vaccinated. Although the overall rate of immunization was low, informational letters about the hepatitis B virus and vaccine were found to be efficacious in increasing hepatitis B immunization rates among students in the setting of a concurrent educational campaign.