Have preferences of girls changed almost 3 years after the much debated start of the HPV vaccination program in The Netherlands? A discrete choice experiment.

OBJECTIVES: To assess how girls' preferences have changed almost 3 years after the much debated start of the human papillomavirus (HPV) vaccination program. METHODS: A discrete choice experiment (DCE) was conducted among girls aged 11-15 years who were invited, or were not yet invited, to get vaccinated. A panel latent class model was used to determine girls' preferences for vaccination based on five characteristics: degree of protection against cervical cancer; duration of protection; risk of mild side-effects; age of vaccination; and the number of required doses of the vaccine. RESULTS: The response rate was 85% (500/592). Most girls preferred vaccination at age 14 years (instead of at age 9 years) and a 2-dose scheme (instead of the current 3-dose scheme). Girls were willing to trade-off 7% (CI: 3.2% to 10.8%) of the degree of protection to have 10% less risk of mild side-effects, and 4% (CI: 1.2% to 5.9%) to receive 2 doses instead of 3 doses. Latent class analyses showed that there was preference heterogeneity among girls, i.e., higher educated girls and HPV vaccinated girls had a higher probability to opt for HPV vaccination at a higher age than lower educated girls or non-vaccinated girls. CONCLUSIONS: Three years after the start of HPV vaccination program the risk of mild side-effects and age at vaccination seem to have become less important. For the Dutch national immunization program, we recommend not to lower the current target age of 12 years. A 2-dose scheme may result in a higher uptake and we recommend that if this scheme is introduced, it needs to receive adequate publicity.

Parents' preferences for vaccinating daughters against human papillomavirus in the Netherlands: a discrete choice experiment.

BACKGROUND: To generate knowledge about potential improvements to human papillomavirus (HPV) vaccination information and organization strategies, we assessed how aspects of HPV vaccination are associated with parents' preferences for their daughters' uptake, and which trade-offs parents are willing to make between these aspects. METHODS: A discrete choice experiment (DCE) was conducted among parents with a daughter aged 10-12 years. Panel mixed logit regression models were used to determine parents' preferences for vaccination. Trade-offs were quantified between four vaccination programme aspects: degree of protection against cervical cancer, duration of protection, risk of serious side-effects, and age of vaccination. RESULTS: Total response rate was 302/983 (31%). All aspects influenced respondents' preferences for HPV vaccination (p < 0.05). Respondents preferred vaccination at age 14 years instead of at a younger age. Respondents were willing to trade-off 11% of the degree of protection to obtain life-time protection instead of 25 years. To obtain a vaccination with a risk of serious side-effects of 1/750,000 instead of 1/150,000, respondents were willing to trade-off 21%. CONCLUSIONS: Uptake may rise if the age ranges for free HPV vaccinations are broadened. Based on the trade-offs parents were willing to make, we conclude that uptake would increase if new evidence indicated outcomes are better than are currently understood, particularly for degree and duration of protection.

Increasing girls' knowledge about human papillomavirus vaccination with a pre-test and a national leaflet: a quasi-experimental study.

BACKGROUND: Adolescent girls are at an age to be involved in the decision about HPV vaccination uptake and therefore need adequate information about the vaccination. This study assesses to what extent reading an official information leaflet about HPV contributes to girls' knowledge levels, and to what extent an increase in knowledge is boosted by a pre-test measurement. METHODS: Participants (girls aged 11-14 years) were systematically allocated to group A that completed a pre-test measurement (12 true/false statements) or to group B that did not complete it. Subsequently, both groups read the HPV leaflet and completed the post-test measurement. RESULTS: The response rate was 237/287 (83%). Pre-test scores in group A (M = 3.6, SD = 1.81, p < 0.001) were lower than post-test mean knowledge scores (0-10) in group B (M = 4.6, SD = 2.05). Post-test knowledge scores in group A were higher than those in group B [6.2 (SD = 2.06) versus 4.6 (SD = 2.05), p < 0.001]. In the post-test measurement, about a third of both groups knew that vaccinations do not give 100% protection against cervical cancer and that the duration of protection is unknown. CONCLUSIONS: Reading the information leaflet had a positive effect on knowledge, even more so when boosted by a pre-test measurement. However, knowledge on the degree and duration of protection against cervical cancer remained limited. Focusing girls' attention on important aspects before they start reading the leaflet (e.g. by including a quiz on the first page) may serve to raise their awareness of these aspects.

Parental decisional strategies regarding HPV vaccination before media debates: a focus group study.

Before the introduction of the human papillomavirus (HPV) vaccine, decisional strategies and factors that could guide HPV vaccination intentions were explored. The authors conducted 4 focus group discussions with 36 parents of children 8-15 years of age. Three groups consisted primarily of Dutch parents and 1 group of only Turkish parents. Discussions followed a semi-structured question route. Results showed that some parents used an approach of systematically seeking information as a way to prepare a decision, whereas others merely relied on trust in the message source. In general, parents believed that it was important to protect their child against negative outcomes that could result from vaccinating or not, and they felt that it is their responsibility to decide about uptake. Perceived susceptibility, vaccine effectiveness, and possibility of serious side effects were most important in the HPV vaccination decision-making process. In conclusion, parents perceived a lack of information and felt insecure about the vaccine's safety and effectiveness. This may result in ambivalent feelings toward HPV vaccination, which, in turn, may lead to postponing decisions about uptake. To facilitate informed decision making, which requires central processing, personally relevant messages about the knowns and unknowns regarding the effects of HPV vaccination should be provided.

Girls' preferences for HPV vaccination: a discrete choice experiment.

A discrete choice experiment was developed to investigate if girls aged 12-16 years make trade-offs between various aspects of human papillomavirus (HPV) vaccination, and to elicit the relative weight that girls' place on these characteristics. Degree of protection against cervical cancer, protection duration, risk of side-effects, and age of vaccination, all proved to influence girls' preferences for HPV vaccination. We found that girls were willing to trade-off 38% protection against cervical cancer to obtain a lifetime protection instead of a protection duration of 6 years, or 17% to obtain an HPV vaccination with a 1 per 750,000 instead of 1 per 150,000 risk of serious side-effects. We conclude that girls indeed made a trade-off between degree of protection and other vaccine characteristics, and that uptake of HPV vaccination may change considerably if girls are supplied with new evidence-based information about the degree of protection against cervical cancer, the protection duration, and the risk of serious side-effects.