Mothers’ Perceptions of their Daughters’ Susceptibility to HPV-related Risk Factors: An Experimental Pretest Comparing Narrative and Statistical Risk Information

Background: In order to promote HPV-vaccination acceptability among mothers of invited girls, we developed a web-based, tailored intervention. This study reports on an experimental pretest for the component of this intervention targeting mothers’ perceptions of their daughters’ susceptibility towards HPV-related risk factors. Statistical versus narrative risk information was pretested as research results remain to be mixed on the surplus value of one type over the other in influencing mothers’ perceptions of their daughters’ susceptibility. Methods: We used data from 375 mothers of girls-to-be invited to the HPV-vaccination round 2014, who were derived from the Dutch National Immunization Register. They were randomly assigned to one of four conditions in a 2 (statistical information: yes or no) × 2 (narrative information: yes or no) between-subjects factorial design. Findings: Mothers who received statistical information felt their daughters were more susceptible towards HPV than mothers who received no statistical information. No main or interaction effects with narrative information were found. The effect of statistical information on mothers’ perceptions of their daughters’ susceptibility towards HPV was not moderated by perceived comprehensibility, credibility or novelty of the risk information, nor mediated by message-induced imaginability, elaboration, personal relevance, or defensive reactions. However, in secondary analyses, in which we only included the statistical and narrative condition, we found personal relevance to mediate the effect of statistical information (independent variable) on mothers’ perceptions of their daughters’ susceptibility towards HPV (dependent variable). Discussion: Statistical risk information appeared most effective in increasing mothers’ perceptions of their daughters’ susceptibility towards HPV and was therefore included in the web-based, tailored intervention promoting HPV-vaccination acceptability.