“In observational studies, you’re basically asking people ‘out in the wild’ about their use of e-cigarettes that they’ve purchased themselves from a corner store, without specific guidance to quit. In the next group of studies, which surveyed smokers using e-cigarettes who did indicate a desire to quit, the researchers also found no effect. Finally, they examined nine clinical trials, which provided some type of e-cigarette, for free, to participants who were specifically encouraged to use the devices to help them quit. “It’s important to recognize that in clinical trials, when certain e-cigarette devices are treated more like medicine, there may actually be an effect on quitting smoking,” said Wang. Also, only seven e-cigarette devices were studied in the clinical trials.