"Positive maternal attitudes toward vaccination have been shown to be associated with higher rates of HPV vaccination," she noted.
Dr. Kester and her colleagues studied a national sample of 501 girls aged 14-17 years and their mothers recruited to an online-based survey in 2010. The mothers and daughters completed surveys asking about number of doses of HPV vaccine the daughter had received, sociodemographic factors, insurance status, and maternal experiences related to HPV infection. The mothers of unvaccinated daughters were asked why they had not had their girls vaccinated. Survey results showed that the mothers were 45 years old on average. The majority were white (76%) and college educated (81%).
According to maternal report, 50% of the daughters had initiated HPV vaccination, defined as having received at least one dose, and 38% had completed vaccination, defined as having received all three doses in the series.
These rates suggest improvement from 2009, Dr. Kester noted, when data from the Centers for Disease Control and Prevention showed an initiation rate of 44% and a completion rate of 27%.
The rate of initiation did not vary significantly with the daughter’s insurance status or according to a variety of maternal factors, such as race/ethnicity, education level, relationship status, geographic location, employment status, or exposure to negative experiences related to HPV (having had an abnormal Pap smear, a colposcopy, or a friend or family member with cervical cancer).
In contrast, the rate of completion differed significantly by maternal race/ethnicity, with about 40% of the daughters of white mothers having completed the series, compared with 25% of daughters of black mothers and 25% of daughters of Hispanic mothers (P less than .001).
Mothers’ most commonly reported reasons for not initiating HPV vaccination for their daughter were concern about vaccine side effects (cited by 36%), fear that it was dangerous (36%), and lack of a recommendation by their provider (34%).
They also cited a belief that the vaccine did not work (13%), not having seen a provider in a long time (12%), concern about eligibility for or cost of the vaccine (11%), and concern that vaccinating would encourage their daughter to have sex (8%).
"There is no evidence from our data that demographic or socioeconomic disparities played a role in vaccination initiation," commented Dr. Kester. "However, we do see that black and Hispanic populations were less likely to complete vaccination."
Taken together, the findings "suggest there is continued need to encourage vaccine uptake as well as need for further educational interventions, at the level of the patient, the provider, and the parent on vaccine benefit, efficacy, and safety," she said. "In addition, this data reminds us that there is a continuing need to evaluate barriers to vaccination initiation and completion, looking at reasons for racial discrepancy of vaccine completion."
Dr. Kahn reported that she is co-principal investigator on two trials in which Merck is providing the vaccine and immunogenicity testing. Dr. Kester reported that some of her coinvestigators are investigators for or receive research funding from Merck.