Smokers who use a texting service to help them quit are twice as likely to be smoke free after six months, compared with those who just receive smoking-cessation reading material, a new study finds.

The overall quit-smoking numbers were low in both groups—11 percent using the texting service, compared with 5 percent in the reading group, Reuters reports. The success rates in the texting group are similar to those generally seen among smokers who receive support from a telephone quitline, the article notes.

“There are a number of proven strategies out there for quitting smoking, and now we have growing evidence that text messaging is another option for quitting,” said lead author Lorien Abroms of George Washington University in Washington, D.C.

The findings are published in the American Journal of Preventive Medicine.

The study included 503 smokers, who were randomly assigned to receive stop-smoking texts, or a National Cancer Institute booklet on smoking cessation. The texting group received encouraging messages in the period leading up to their quit date. In the week after they quit, they received many supportive messages each day. After 10 weeks, they received messages once a week.

If the smokers were feeling the urge to smoke, they could text “CRAVE” and receive a response such as a trivia game or a tip. Texting “STAT” would allow them to see their quitting statistics, while texting “SMOKED” alerted the researchers that they had a cigarette, and might need to restart the program.

Participants in the study were encouraged to use additional smoking cessation methods, such as nicotine patches, telephone quitlines and counseling.

To verify whether smokers had quit, participants provided a saliva sample, which was tested for a byproduct of nicotine.