OBJECTIVES To quantify preferences for influenza vaccine attributes among healthcare providers (HCPs) in the United States (US).
METHODS Using a discrete-choice experiment (DCE), US HCPs were presented with a series of experimentally-designed pairs of hypothetical influenza vaccines comprising five attributes with varying levels: absolute vaccine efficacy (AVE) (15%-60% of influenza infections prevented), hospitalization prevention (same as most other vaccines, more than most other vaccines), durability (protection fades within 6 months, constant protection for at least 6 months), and side effects (risk of moderate-to-severe injection site reactions [ISR] [0%-50%] and risk of flu-like symptoms [FLS] due to the vaccine [0%-60%]). In each choice question, respondents selected their preferred vaccine or “no flu vaccine” for one of two patients described in vignettes. Random-parameters logit analysis results were used to calculate conditional relative attribute importance (CRI) out of 100% and maximum acceptable risks of vaccine side effects in exchange for improvements in vaccine efficacy.
RESULTS The sample included 299 US HCPs (144 physicians and 5 physician assistants [primary care, internal medicine, family medicine, general practice, or geriatrics]), 150 pharmacists [all practice settings]). Respondents preferred either influenza vaccine over no vaccine in 95.3% of DCE questions. HCPs placed greatest importance on avoiding risk of FLS (CRI, 39.8%) and increasing AVE (CRI, 37.4%), followed by avoiding ISR risk (CRI, 14.1%). Durability (CRI, 5.1%) and hospitalization prevention (CRI, 3.5%) were least important. For an improvement in AVE from 15% to 25%, HCPs were willing to accept a 44.7% risk of ISR or a 21% risk of FLS. For an improvement in AVE from 25% to 50%, HCPs were willing to accept > 50% risk of ISR or a 26.8% risk of FLS.
CONCLUSION HCPs in the US were more likely to accept increases in vaccine-related risks of FLS than ISR in exchange for improved AVE.
