Patient preferences toward herpes zoster vaccination among individuals aged 50 years or older in South Korea: Findings from a discrete choice experiment.

In South Korea, the increasing incidence of herpes zoster (HZ) and aging population warrant consideration of HZ vaccination for older adults. There is a need to understand the HZ vaccine-related preferences of adults aged ≥50 years and adult children (working or financially independent adults contributing to healthcare decision-making for their parents aged ≥50 years). A discrete choice experiment was conducted to elicit HZ vaccine preferences of the HZ-naïve general public aged ≥50 years (n = 500), current/former HZ patients aged ≥50 years (n = 150), and adult children (n = 150). An online questionnaire was administered through March-May 2023; for each preference-elicitation question, respondents selected between three hypothetical HZ vaccine profiles, characterized by five attributes with varying levels, or "no vaccine". Respondents generally accepted an increased number of doses (from one to two) for a longer protection duration (from ≥4 to ≥7 or ≥10 years). By mean relative importance (RI), protection duration (RI: 37.1%; 95% confidence interval [CI]: 36.0%, 38.1%), lifetime HZ risk reduction (27.3%; 95% CI: 26.3%, 28.4%) and short-term side effects (14.9%; 95% CI: 14.1%, 15.6%) had the strongest impact on respondents' HZ vaccine decision-making. Adult children viewed short-term side effects with significantly greater RI than the general public and current/former HZ patients (19.1%, 13.5%, 15.2%, respectively, p < .001). Respondents with selected comorbidities placed higher RI than those without comorbidities on protection duration (39.3% versus 34.2%, p < .001) and lower RI on prevention of HZ-related complications (8.7% versus 10.4%, p = .007). Findings may guide health policy design/refinement and physician-patient conversations on HZ vaccination/vaccines.