DIFFERENCES IN DEMOGRAPHICS AND COVID-19 HISTORY BETWEEN ENGAGED AND NON-ENGAGED US RESPONDENTS IN A DISCRETE CHOICE EXPERIMENT OF COVID-19 PRE/POST-EXPOSURE PROPHYLAXIS
Author(s)
Michelle E. Orme, PhD1, Rodolphe Perard, MSc, PharmD2, Mark Orme, -1.
1ICERA Consulting Ltd, Swindon, United Kingdom, 2SHIONOGI B.V., London, United Kingdom.
1ICERA Consulting Ltd, Swindon, United Kingdom, 2SHIONOGI B.V., London, United Kingdom.
OBJECTIVES: A discrete choice experiment (DCE) of COVID-19 pre/post-exposure prophylaxis (PrEP/PEP) included a no-treatment/opt-out choice to account for respondents who would not engage with treatment alternatives. This analysis quantifies the differences in demographics and COVID-19 history between non-engaged and engaged respondents.
METHODS: Data were from an online survey of US adults (May - June 2025). Non-engaged respondents ('Non-Traders') were pre-defined as choosing no treatment in ≥4/8 main choice sets. Twenty-two demographic and COVID-19 history covariates were pre-specified. Continuous age was tested with Welch t-test; categorical variables with Pearson chi-square (Fisher's exact for 2×2 tables) plus per-level two-sample z-tests. Wilson 95% confidence intervals (CIs) are reported for proportions, normal-approximation 95% CIs for differences. A Bonferroni-adjusted alpha (0.05/22 = 0.0023) controlled the family-wise error rate.
RESULTS: Of 10,475 respondents, 2,019 (19.3%) were Non-Traders and 8,456 (80.7%) Traders. COVID-19 vaccination uptake was lower in Non-Traders (50.5% vs Traders 86.2%; −35.7 percentage points (pp); 95% CI −38.0, −33.3; p<0.001). Among COVID-19-infected respondents, Traders were more likely to have received medication (+6.77 pp; 95% CI +5.34, +8.19; p<0.001) and to report severe symptoms (+2.32 pp; 95% CI +0.77, +3.88; p=0.005). Non-Traders were more likely to be White (+6.7 pp; 95% CI +4.8, +8.5) and less likely to hold a post-graduate qualification (−6.5 pp; 95% CI −8.1, −4.9); both p<0.001. Age-group distribution differed (more 18-24 and 65+ in Traders, more 45-64 in Non-Traders; p<0.001); mean age was similar (Non-Traders 57.8 vs Traders 57.5 years; p=0.44 for difference). No differences for US region, household size, ever-infected, Long COVID or hospitalisation (all p<0.05).
CONCLUSIONS: Non-engaged DCE respondents differed from engaged respondents in COVID-19 vaccination and treatment uptake, and by race/ethnicity, education, age-group distribution. The reasons for non-engagement requires further investigation.
METHODS: Data were from an online survey of US adults (May - June 2025). Non-engaged respondents ('Non-Traders') were pre-defined as choosing no treatment in ≥4/8 main choice sets. Twenty-two demographic and COVID-19 history covariates were pre-specified. Continuous age was tested with Welch t-test; categorical variables with Pearson chi-square (Fisher's exact for 2×2 tables) plus per-level two-sample z-tests. Wilson 95% confidence intervals (CIs) are reported for proportions, normal-approximation 95% CIs for differences. A Bonferroni-adjusted alpha (0.05/22 = 0.0023) controlled the family-wise error rate.
RESULTS: Of 10,475 respondents, 2,019 (19.3%) were Non-Traders and 8,456 (80.7%) Traders. COVID-19 vaccination uptake was lower in Non-Traders (50.5% vs Traders 86.2%; −35.7 percentage points (pp); 95% CI −38.0, −33.3; p<0.001). Among COVID-19-infected respondents, Traders were more likely to have received medication (+6.77 pp; 95% CI +5.34, +8.19; p<0.001) and to report severe symptoms (+2.32 pp; 95% CI +0.77, +3.88; p=0.005). Non-Traders were more likely to be White (+6.7 pp; 95% CI +4.8, +8.5) and less likely to hold a post-graduate qualification (−6.5 pp; 95% CI −8.1, −4.9); both p<0.001. Age-group distribution differed (more 18-24 and 65+ in Traders, more 45-64 in Non-Traders; p<0.001); mean age was similar (Non-Traders 57.8 vs Traders 57.5 years; p=0.44 for difference). No differences for US region, household size, ever-infected, Long COVID or hospitalisation (all p<0.05).
CONCLUSIONS: Non-engaged DCE respondents differed from engaged respondents in COVID-19 vaccination and treatment uptake, and by race/ethnicity, education, age-group distribution. The reasons for non-engagement requires further investigation.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
PCR10
Topic
Patient-Centered Research
Topic Subcategory
Patient Behavior and Incentives, Patient Engagement
Disease
Infectious Disease (non-vaccine), No Additional Disease & Conditions/Specialized Treatment Areas