Are intelligent people more likely to get vaccinated? The association between COVID-19 vaccine adherence and...

Since vaccination adherence is crucial in reducing morbidity and mortality during a pandemic, we characterized the association between demographic, intelligence, and personal attributes and COVID-19 vaccination adherence among young adults.

Cohort study including vaccination data of 185,061 personnel, collected during 13 months of COVID-19 vaccination campaign, while a wide array of vaccination incentives were offered. The effect of demographic data (age, gender and socioeconomic status), military medical fitness - fit for combat service, administrative service, or unfit (volunteering), general intelligence score (GIS) and military social score (MSS) assessing social abilities, on vaccine adherence (allocating by IMOH guidelines) was examined.

Adherent (vs. nonadherent) personnel presented higher GIS (mean 5.68 ± 1.84 vs. 4.72 ± 1.91) and MSS (median 26 (IQR 23-29) vs. 24 (IQR 19-26)), p < 0.001 for both. Higher intelligence was the strongest predictor for vaccine adherence (OR = 5.38, 95 %CI 5.11-5.67, p < 0.001). The probability for vaccine adherence increased in association with escalating GIS scores, with highest GIS females more likely to adhere to vaccination than same-level males (OR = 5.66, 95 %CI 5.09-6.28 vs. OR = 3.69, 95 %CI 3.45-3.94, respectively, p < 0.001 for both). Medically fit service-members were approximately three times as likely to be adherent than volunteering personnel (OR = 2.90 (95 %CI 2.65-3.17) for administrative and OR = 2.94 (95 %CI 2.70-3.21) for combative fitness, p < 0.001 for both).

During a COVID-19 vaccination campaign, addressing vaccine hesitancy contributing factors and providing wide vaccine availability, GIS and physical fitness had the strongest association with vaccination adherence among young adults. When planning future vaccination campaigns, implementing these insights should be considered to improve adherence.