From Qualitative Research to Quantitative Preference Elicitation: An Example in Invasive Meningococcal Disease.

Qualitative research is fundamental for designing discrete choice experiments (DCEs) but is often underreported in the preference literature. We developed a DCE to elicit preferences for vaccination against invasive meningococcal disease (IMD) among adolescents and young people (AYP) and parents and legal guardians (PLG) in the United States. This article reports the targeted literature review and qualitative interviews that informed the DCE design and demonstrates how to apply the recent reporting guidelines for qualitative developmental work in preference studies. This study included two parts: a targeted literature review and qualitative interviews. The Medline and Embase databases were searched for quantitative and qualitative studies on IMD and immunization. The results of the targeted literature review informed a qualitative interview guide. Sixty-minute, online, semi-structured interviews with AYP and PLG were used to identify themes related to willingness to be vaccinated against IMD. Participants were recruited through a third-party recruiter's database and commercial online panels. Interviews included vignettes about IMD and vaccinations and three thresholding exercises examining the effect of incidence rate, disability rate, and fatality rate on vaccination preferences. Participant responses related to the themes were counted. The targeted literature review identified 31 concepts that were synthesized into six topics for the qualitative interviews. Twenty AYP aged 16-23 years and 20 PLG of adolescents aged 11-17 years were interviewed. Four themes related to willingness to be vaccinated emerged: attitudes towards vaccination, knowledge and information, perception of IMD, and vaccine attributes. Most participants were concerned about IMD (AYP 60%; PLG 85%) and had positive views of vaccination (AYP 80%; PLG 60%). Ninety percent of AYP and 75% of PLG always chose vaccination over no vaccination, independent of IMD incidence rate, disability rate, or fatality rate. Willingness to be vaccinated against IMD was affected by vaccine attributes but largely insensitive to IMD incidence and severity. This article provides an example of how to apply the recent reporting guidelines for qualitative developmental work in preference studies, with 21 out of 22 items in the guidelines being considered.

Coulter J ，Whichello C ，Heidenreich S ，Hauber B ，Michaels-Igbokwe C ，Cappelleri JC ，Peyrani P ，Vespa Presa J ，Venkatraman M ，Schley K ... -  《-》

Preferences of US adolescents and parents for vaccination against invasive meningococcal disease.

Percentage uptake of some meningococcal vaccines is low in the US. Understanding what drives vaccination preferences may help to increase vaccination rates. To determine how attributes of meningococcal vaccines and the availability of a pentavalent (MenABCWY) vaccine profile drive adolescents' and young people's (AYP's) willingness to be vaccinated and parents' and legal guardians' (PLG') willingness for their child to be vaccinated (WTV). To also explore how preferences for meningococcal vaccines vary by participant characteristics. Vaccine preferences were elicited in a discrete choice experiment (DCE) with AYP aged 16-23 years and PLG of adolescents aged 11-17 years. Participants chose between two hypothetical vaccine profiles that differed in level of protection, dosing, and risks of mild-to-moderate and severe side effects, and a no vaccination profile. Main outcome measures were relative attribute importance (RAI) and WTV. RAI measured the maximum contribution of an attribute to vaccination choice relative to other attributes. WTV compared predicted choice probabilities for the three vaccine profiles. 407 AYP and 394 PLG participated (50.9% male, 78.4% White/Caucasian). Irrespective of vaccine attributes, 59.5% always opted into vaccination and 3.6% always opted out of vaccination. The most important attributes were level of protection (RAI: 33.7%) and risk of mild-to-moderate side effects (RAI: 32.3%). Dosing was more important to PLG (RAI: 5.9%) than AYP (RAI: 2.0%; p < .01). Adding a pentavalent vaccine alternative increased WTV by 3.7 percentage points (PP) for PLG, 2.4 PP for AYP, 16.4 PP for vaccine-hesitant participants, 13.4 PP for participants without health insurance, and 9.6 PP for adults. Level of protection and risk of mild-to-moderate side effects were the most important vaccine attributes. Adding a pentavalent vaccine alternative increased WTV particularly among adults, individuals who were vaccine-hesitant, and individuals without health insurance.

Schley K ，Whichello C ，Hauber B ，Krucien N ，Cappelleri JC ，Peyrani P ，Presa JV ，Coulter J ，Heidenreich S ... -  《-》

Parental awareness and utilization of meningococcal serogroup B vaccines in the United States.

Srivastava A ，Dempsey A ，Galitsky A ，Fahimi M ，Huang L ... -  《BMC PUBLIC HEALTH》

Adolescent, parent and societal preferences and willingness to pay for meningococcal B vaccine: A Discrete Choice Experiment.

Meningococcal B (MenB) vaccines have been licensed in many countries with private purchase the only option until recently, when a funded programme was introduced in the UK. The aim of this study was to explore adolescent/parental values for a variety of salient vaccine attributes (cost, effectiveness, side effect profile) to assess preferences and willingness-to-pay (WTP) for a MenB vaccine. A national cross-sectional population study was conducted in Australia using Discrete Choice Experiment methodology to assess adolescent/parent/adult preferences for attributes related to MenB vaccine. 2003 adults and 502 adolescents completed the survey in 2013. The majority of participants were willing to be vaccinated with MenB vaccine with vaccination opt-out chosen by 11.9% of adolescents and parents, and 18.2% of non-parent adults. A mixed logit regression model examining adolescent/adult preferences indicated consistent findings; the higher the effectiveness, the longer the duration of protection, the less chance of adverse events and the lower the cost, the more likely respondents were to agree to vaccination. For an ideal MenB vaccine, including the most favoured level of each attribute summed together (90% effectiveness, 10 year duration, 1 injection, no adverse events) adolescents would pay AU$251.60 and parents AU$295.10. Adolescents and parents would pay AU$90.70 or AU$127.20 for 90% vaccine effectiveness vs AU$18.50 or AU$16.70 for 70% effectiveness and would want to be financially compensated for 50% effectiveness; pay AU$63.30 or AU$76.40 for 10 years protection; and pay AU$48.50 or AU$49.20 for no vaccine related adverse events. A slight fever post vaccination was a preferred choice with parents and adolescents willing to pay AU$9.60 or AU$12.30 for this attribute. Vaccine effectiveness, adverse events and duration of immunity are important drivers for parental and adolescent decisions about WTP for MenB vaccine and should be included in discussions on the benefits, risks and cost.

Marshall HS ，Chen G ，Clarke M ，Ratcliffe J ... -  《-》

Quantifying Stated Preferences for Meningococcal Vaccines Among Adolescents/Young Adults and Parents of Adolescents in the United States: A Discrete Choice Experiment.

Invasive meningococcal disease (IMD) is a severe and life-threatening disease. In the United States (US), vaccine coverage with MenACWY and MenB meningococcal vaccines is suboptimal among adolescents/young adults aged 16-23 years. A combined meningococcal vaccine (MenABCWY) could increase convenience (e.g., fewer injections) and improve coverage. The objective was to quantify preferences for hypothetical meningococcal vaccine profiles among adolescents/young adults and parents. An online discrete choice experiment was conducted among 16- to 23-year-olds, and parents of 16- to 18-year-olds. Attributes (3 × 4) and levels (1 × 2) were based on the literature and focus groups. Participants made ten pair-wise forced trade-off choices, systematically varied using a D-optimal design. Random parameter logit quantified the relative importance of vaccination attributes and estimated the trade-offs. Differences in preferences by subgroups were assessed. Totals of 300 adolescents and young adults (median age 20 years) and 300 parents (median age 46 years) completed the survey. Overall, 89.6% of 16- to 23-year-olds and 69.1% of parents preferred a simplified hypothetical meningococcal vaccination profile, e.g., with fewer injections (3 vs. 4) and fewer healthcare provider (HCP) visits (2-3 vs. 4). Having HCP advice and clear Centers for Disease Control and Prevention recommendations impacted vaccination choice, with both groups reporting high trust in HCP information (83.3% among 16- to 23-year-olds; 98.7% among parents). Barriers to vaccination included lack of HCP advice or awareness of meningococcal vaccines, and income level and out-of-pocket costs for parents. Adolescents/young adults and parents demonstrated a significant preference for a meningococcal vaccine that is more convenient (such as combined MenABCWY). Parents' vaccination preferences differed by income level and out-of-pocket costs, suggesting financial barriers to vaccination may exist which could result in IMD prevention inequalities. Findings from this study provide important information to support patient-facing informed policy discussions. A simplified vaccination schedule and strong recommendation could help improve vaccine uptake, schedule compliance, disease prevention, and reduce inequalities in IMD risk and prevention. A graphical abstract is available with this article.

Begum S ，Cabrera ES ，Restrepo OH ，Burman C ，Sohn WY ，Kuylen E ，Shah H ，Kocaata Z ... -  《-》