Lottery-Based Incentives and COVID-19 Vaccination Rates in Ohio

Walkey AJ, Law A, Bosch NA Lottery-based incentives and COVID-19 vaccination rates in Ohio. Jama. Published online July 2, 2021. doi: 10.1001 / jama.2021.11048

Commentary.

On May 12, 2021, Ohio announced a lottery system that pays up to $1 million to randomly selected vaccinees, but it is unclear whether the policy has increased vaccination rates. The study, deemed not to be a human experiment by the Boston University Medical Campus Institutional Review Board, used data from the Centers for Disease Control and Prevention's COVID-19 Vaccine Tracker4 to identify the first daily dose of COVID-19 vaccine in adults 18 years and older.

Ohio vaccination rates were compared to U.S. vaccination rates, adjusted for the day of the week, and to account for the first-order autocorrelation that exists between vaccination rates on consecutive days.

All statistical tests were two-tailed with an alpha level of .05 using R version 4.0.2 (R Project for Statistical Computing).

The results show that from April 15, 2021 to June 9, 2021, the daily adult immunization rate decreased from 485/100,000 to 101/100,000 in Ohio and from 700/100,000 to 97/100,000 in the state without lottery incentives.

There was a significant decrease in both Ohio and the U.S. Since May 12, adult vaccination rates have not increased significantly in either Ohio or the U.S.

The analysis shows that after the May 12 lottery announcement, the rate of decline in vaccination slowed significantly more in the U.S. than in Ohio. The slower decline in adult vaccination rates in the US may suggest that the expansion of vaccination eligibility to adolescents was also associated with an increase in adult vaccination.

These results are in contrast to a previous report of increased vaccination in Ohio,2 which did not explain the concurrent expansion of vaccination eligibility among adolescents.