Trial Information

Brief Interventions to Increase HPV Vaccine Acceptance in School-based Health Centers in Adolescents

The proposed study will employ a randomized, full factorial experimental design to examine
the effects of brief message interventions on parents' acceptance of the first dose of HPV
vaccine for their adolescents aged 11-14 years, as well as follow through with subsequent
doses. Specifically, the study will employ a 2 x 2 experimental design, in which
participants will be assigned randomly to one of two different message sidedness conditions
(1 sided vs. 2 sided) and two social compliance conditions (high compliance request [HCR]
vs. noHCR). The interventions will be administered by a bilingual research assistant who
will read, verbatim, scripts provided to them. Computer assisted telephone interview (CATI)
will be used to gather demographic and background information as well as parental health
beliefs regarding preexisting worries about HPV vaccine leading to safety concerns
(moderator variable) prior to administration of the interventions. After the interventions,
additional health beliefs will be assessed (mediators).

1. A greater proportion of girls as compared to boys will receive a first dose of vaccine.

2. Among both girls and boys who receive a first dose of Gardasil™, no differences in
completion rates will be detected.

3. The social compliance intervention to be more effective with parents of girls as
compared to parents of boys. This prediction of a differential effect is based on the
fact that cervical cancer will be seen as a more serious and less stigmatizing
condition than genital warts.

In summary, the implementation of this protocol will allow us to systematically examine the
use of two different interventions on parents of both boys and girls. Thus, parents (n=800)
of 11-14 year old girls and boys will be randomized to the two sets of interventions,
resulting in a 2 X 2 design: message sidedness (1-sided; 2-sided) and HCR (yes; no).