Preferences for herpes zoster vaccination among adults aged 50 years and older in the United States: results from a discrete choice experiment.

BackgroundMost adults, and disproportionately fewer African-Americans, have not received herpes zoster (HZ) vaccination despite current recommendations. This study (GSK study identifiers: 208677/HO-17-18066) assessed HZ vaccination preferences among adults aged ≥ 50 years.Research design and methodsIn this discrete choice experiment, respondents chose among a "no vaccine" option and two HZ vaccine profiles, characterized by seven attributes, in a series of choice questions. Random-parameters logit results were used to predict likely vaccine uptake. Subgroup and latent class analysis of African-American's preferences were performed.ResultsThe preference weight for choosing HZ vaccines over no vaccine was statistically significant among the 1,454 respondents (71.9% whites; 25.2% African-Americans). Out-of-pocket (OOP) cost and vaccine effectiveness (VE) were the most important attributes. The African-American and the non-African-American subgroups had statistically significant differences in preferences (χ2 = 59.91, p < 0.001), mainly driven by OOP cost and VE. Latent class analysis identified 3 groups of African-American respondents with systematically different preferences; two comprised likely-vaccinators, with one being more cost sensitive at lower price thresholds, and one likely non-vaccinators.ConclusionsFor all respondents, HZ vaccine choices were most sensitive to total OOP cost, followed by VE.