The majority of Maine voters opted last week to uphold a law that eliminates nonmedical exemptions for required childhood vaccinations.

That means one-fourth of voters were not in favor of this measure, which is why it is important to take into account psychological research that may persuade the naysayers to follow the law and get their kids immunized.

One of the most critical – and controversial – vaccines is MMR, which protects against measles, mumps and rubella. To understand the problem that Maine legislators were seeking to address, look no further than last year’s measles outbreak, which touched the state. The Maine Department of Health and Human Services reported that in the fall of 2018, only 93.8 percent of kindergarten children in the state had been vaccinated for measles, mumps and rubella, while 674 kindergartners were granted exemptions from receiving the vaccination. That falls below the 95 percent vaccination rate required to prevent the spread of the disease among those not vaccinated.

And Maine’s rate of pertussis, a vaccine-preventable disease that’s also known as whooping cough, is now eight times the national average.

Research in psychology shows us that humans have both analytical and emotional ways of absorbing information and evaluating risks. We tend to be less concerned about diseases we know about, such as the flu, than we are about new diseases that allow us to imagine catastrophic consequences. We also tend to devalue vaccines precisely because they have been so successful at eradicating diseases many of us have never seen, such as smallpox and polio. Research shows us that the following factors can motivate people to get vaccinated:

• Establishing incentives and consequences. Research shows that both incentives and consequences are effective at persuading people to get vaccinated. For example, requiring that children are vaccinated before they can enroll in public schools has been extremely effective. That is why the outcome of Maine’s election was so important. But we also need to get creative about offering incentives to further encourage vaccinations.

• Getting recommendations from health care providers. This is one of the best ways to get people vaccinated, because we trust the opinion of doctors, nurses and physician assistants. The recommendation for vaccination from health care providers is typically viewed as authoritative evidence that vaccines work and are safe. Such prompts are also helpful in that people can get the vaccines when they are already at their doctor’s office.

• Setting up reminders. We lead busy lives, so it is important that health care providers reach out to patients or send emails to remind them when it is time for vaccinations. Scheduling appointments well in advance can also be effective, as it requires people to opt out of a vaccine rather than having to call and schedule an appointment.

• Removing barriers to vaccinations. Research shows that one of the best ways to get more people vaccinated is to make vaccines more accessible. This means establishing temporary clinics in as many settings as possible – schools, town fairs, workplaces and churches, for example – to allow people to overcome any logistical obstacles they might face. It also means removing financial barriers by having health insurance plans cover vaccines that can prevent diseases, thus saving money down the line.

While these strategies may seem simple, putting them in place takes resources and effort. The American Psychological Association will continue to invest in the best in psychological science to encourage parents to get their children vaccinated. But getting people to follow through for themselves and their children will require the active participation of public policymakers, employers and community leaders. Psychologists have conducted the science; now we need our leaders to put it in action.