(CTV News) — New U.S. research has found that using e-cigarettes can be effective in helping smokers quit, but success can depend on how much smokers use them.

Carried out by researchers from Georgetown Lombardi Comprehensive Cancer Center, the team used data from the national Tobacco Use Supplement to the Current Population Survey (TUS-CPS) to look at the relationship between the frequency of e-cigarette use, the number of attempts to quit cigarettes, and cigarette abstinence.

The study, published online in Nicotine & Tobacco Research, included 24,500 current or recent former cigarette smokers taken from the TUS-CPS survey, the largest sample of smokers studied to date.

The team also looked at research published back in July in the British Medical Journal, which, according to the new study’s lead author David Levy, together helped provide some of the strongest evidence found so far on the link between use of e-cigarettes and quitting smoking.

The data showed that having made an attempt to quit smoking was more likely among smokers using e-cigarettes than non-users. (…)