Text messages can give smokers the constant reminders they need to stay focused on quitting and double their chances of kicking the butt, a new study has found.

More than 11 per cent of smokers who used a text- messaging programme to help them quit did so and remained smoke free at the end of a six-month study as compared to just 5 per cent of controls, according to researchers at Milken Institute School of Public Health at the George Washington University (Milken Institute SPH).

"Text messages seem to give smokers the constant reminders they need to stay focused on quitting," said Lorien C Abroms, an associate professor of prevention and community health at Milken Institute SPH and lead author of the study.

"However, additional studies must be done to confirm this result and to look at how these programmes work when coupled with other established anti-smoking therapies," Abroms said.

Smokers trying to quit can turn to the tried-and-true methods like phone counselling through a quit line and nicotine replacement therapies, but increasingly the evidence is building for using text messaging on mobile phones.

Text-messaging programmes, like Text2Quit, work by sending advice, reminders and tips that help smokers resist the craving for a cigarette and stick to a quit date.

Despite the widespread use of anti-smoking apps and texting programmes, there had been no long-term studies of such programmes in the US.

Most of the existing research on such programmes were small in size, lacked a control group, and did not biochemically verify smoking status, Abroms said.

To help address such gaps, Abroms and her colleagues decided to carry out a large, randomised trial of a text-messaging programme.

They recruited 503 smokers on the internet and randomised them to receive either a text-messaging programme called Text2Quit or self-help material aimed at getting smokers to quit.

At the end of six months, the researchers sent out a survey to find out how many people in each group had stopped smoking.

They found that people using the text-messaging programme had a much higher likelihood of quitting compared to the control group, a finding that suggests that text-messaging programmes can provide an important boost for people struggling with a tobacco habit.

To verify the positive results, the researchers collected a sample of saliva from smokers who reported quitting and tested it to see if it showed any evidence of a nicotine byproduct called cotinine.

The quit rates for people with biochemically confirmed abstinence at the six month mark were still two times higher than the control group, Abroms said.