The number of weekly vaccinations in Colorado dropped by more than two-thirds between the start and end of the state’s vaccine lottery, following nearly the same trajectory set in the weeks before Gov. Jared Polis announced the $1 million drawings.
While some states saw larger apparent benefits from their lotteries than Colorado, it’s difficult to prove prizes were the cause. Colorado expanded its partnerships to reach rural and underserved communities at roughly the same time it announced the drawings, and the other states offering lotteries most likely also took other steps.
About 155,000 people received a vaccine during the week ending May 23, the last week before Polis announced on May 25 that the state would draw five $1 million winners, according to the Colorado Department of Public Health and Environment.
In the week ending July 4 — the last with data on the state’s vaccine dashboard — only about 49,000 people got a shot.
That’s roughly a 68% decrease, suggesting the lottery didn’t dramatically improve the existing trajectory.
New vaccinations had fallen by about 62% in the six weeks preceding the announcement. It’s possible they would have dropped even further without a lottery, but that’s difficult to prove either way.
Conor Cahill, a spokesman for the governor’s office, said the state’s Joint Vaccine Task Force had projected in May that new vaccinations would drop even further without additional efforts to boost demand. Colorado and other states with lotteries have seen their weekly vaccinations fall more slowly than states that didn’t have drawings, he said.
“The drawing drew national attention and contributed to our successful efforts to reach a 70% vaccination rate by July 4,” he said in a statement. “It also gave us the opportunity to remind Coloradans that while a million dollars or a $50,000 scholarship is life-changing, the vaccine itself is life-saving. This made an impact.”
Almost 69% of Colorado residents who are 12 or older have had at least one shot, and 62% are fully vaccinated, according to data from the Centers for Disease Control and Prevention.
Polis has said the lottery did more to improve vaccination rates than putting the roughly $6.25 million used for the jackpots and college scholarships into additional advertising. The money came from a federal stimulus bill.
It’s reasonable for states to use lotteries to nudge people who aren’t opposed to getting the vaccine but haven’t done it yet, particularly since the prize money is a relatively small percentage of what they’re spending on COVID-19 response, said Iwan Barankay, an economist at the University of Pennsylvania who has studied how incentives affect health behavior.
People generally are more motivated by a slim chance at a large reward than by a guaranteed small reward, but incentives alone aren’t likely to be enough to reach states’ vaccination goals, he said.
“For vaccines, we need to try all avenues,” he said. “Even if we get a small effect from these lotteries, they’re worthwhile.”
Studies using incentives to encourage a healthy behavior, like getting people prescribed statins for their high cholesterol to take them regularly, found people with difficulties like irregular work schedules or multiple health conditions are less likely to be able to follow through, even if they find the incentive attractive, Barankay said.
The same thing likely applies with vaccines, because a person who can’t take time off work, doesn’t have transportation or isn’t able to find necessary information about getting vaccinated probably won’t be able to clear those hurdles — even if they’d like to be in the lottery, he said.
But it’s not clear if ease of access explained why some states saw a greater benefit from their vaccine lotteries than others.
In Colorado, the percentage of people 12 and older who had gotten at least one dose of the vaccine increased by about 6.9 points, from 61.4% on May 24 to 68.3% on Monday. That was the 18th-largest increase nationwide for that period, according to a Post analysis of CDC data.
Some states with lotteries saw larger bumps. Three of the five states that most improved the percentage of their eligible residents that had gotten at least one shot — Washington, New York and California — offered million-dollar lotteries, and the other two, Maryland and New Mexico, offered smaller jackpots to more people.
Other states that offered lotteries performed below the national average, though it’s possible they could see additional benefits, since they haven’t drawn all of their winners. Kentucky, Louisiana, Nevada, North Carolina and West Virginia have yet to draw their final winners, and Michigan and Massachusetts recently announced they would hold vaccine lotteries, according to The New York Times.
Ultimately, making it easier to get the vaccine and possibly setting mandates in workplaces and schools could make a bigger difference than offering prizes, Barankay said. State governments have been reluctant to impose mandates, though, and some health facilities that require employees to get vaccinated have faced a backlash, perhaps making persuasion a more appealing tool.
“I don’t think (unvaccinated people) are lazy or lack focus on the issue, or don’t value their future health or the health of others around them, which is when incentives would be useful – instead they are facing real logistical and personal barriers that incentives don’t address,” he said. “We have to continue making vaccines easy to get and bring the shots to those people.”