Researchers following more than 9,000 mostly low-income kids found that when parents got a series of text messages starting early in the 2010-2011 flu season, their kids were more likely to have gotten a flu shot by the end of that season than children of parents who didn't receive the texts.

The researcher who led the study said that text messages may be more effective than calling a household or sending a reminder letter because texts are sent to a specific person and stored in the phone.

"You can reach so many families and patients at one time in an automated, efficient fashion and you tailor it to what the families need," said Dr. Melissa Stockwell, an assistant professor of pediatrics and of population and family health at the Columbia University Mailman School of Public Health in New York.

Although the difference in vaccination rates between the two groups of kids was relatively small, an editorial accompanying the study in the Journal of the American Medical Association called the results promising.

"The potential is substantial, and in the right setting with automated, integrated information systems, text message reminders can target large numbers of patients at relatively low cost," wrote Drs. Peter Szilagyi and William Adams from the University of Rochester School of Medicine and Dentistry and the Boston University School of Medicine, respectively.

For their study, Stockwell's team enrolled 9,213 kids and teens between six months and 18 years old at four community-based clinics in New York before the start of flu season in 2010. Typically, the season begins in October and extends through March, but peaks in January and February.

More than half of the kids and teens came from Spanish-speaking families and almost 90 percent were publicly insured.

Parents of about half the kids and teens received weekly text messages, and all parents in the text group as well as a comparison group received a reminder phone call in November.

The researchers created a software program that combined information from the clinics' electronic health records and New York City's immunization database to send parents five texts that were personalized based on the information in their medical records.

The first three texts focused on educating the parents about vaccine safety, and emphasized the seriousness of flu in children. The messages were sent in either English or Spanish.

According to Stockwell, the texts attempted to clear up common misconceptions, like that the flu is just a bad cold and that the flu shot can cause the flu.

The last two texts told parents about weekly Saturday vaccine clinics held at one of the four centers in the fall. In January, if a child was still not vaccinated, another two text messages were sent reminding parents about getting the vaccine and when the next clinics would be held.

Of the roughly 4,600 kids and teens in the group receiving texts, about 760 parents were unreachable or declined future messages.

At the end of the study in March 2011, about 44 percent of the kids and teens in the texting group were vaccinated and 40 percent of those whose parents did not receive texts got the shot.

Stockwell's team cautioned that their results may underestimate the potential effectiveness of the texts because not every family was told about all vaccine clinic dates to prevent overcrowding. Their results are also limited to a single medical system and might not be applicable to the general public.

In their editorial, Szilagyi and Adams also said the study's design might have diminished the text messages' effect.

But Adams told Reuters Health that text message reminders or similar electronic interactions between healthcare workers and patients will become more and more common.

"It's pretty quickly not going to be research, it's going to be everyday healthcare," he said.

According to Szilagyi and Adams, if the new study's results were applied across the U.S., an additional 2.5 million kids and teens would be vaccinated against the flu.

The U.S. Centers for Disease Control and Prevention supports universal flu vaccination, which means everyone over six months old -- with a few exceptions -- should get vaccinated every year.

Experts say it's especially important to vaccinate children against flu, not only to protect them from serious illness, but also because children often spread the flu to vulnerable adults -- like pregnant women and the elderly -- who are at the highest risk of dying as a result of a flu infection.

Stockwell told Reuters Health that the benefits of instituting a text messaging system like the one her group created could outweigh the costs.

In total, the researchers spent $7,000 to create the system, $270 per week to monitor it and $165 to send the more than 23,000 text messages.

"If you're a big enough organization the upfront cost isn't that big of a deal," she said.

SOURCE: bit.ly/IzZWKK Journal of the American Medical Association, online April 24, 2012.

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