In an op-ed piece published in the Wall Street Journal, Dr. Pamela Ling - a professor of medicine with the Center for Tobacco Control Research and Education at the University of California, San Francisco - argues that electronic cigarettes hinder, rather than aid smoking cessation and that smokers should use more effective methods such as nicotine patches.
The basis of her conclusion is as follows: "There is only one randomized clinical trial—the
type of study considered most reliable—comparing e-cigarettes with a
nicotine patch. It showed low quit rates and virtually no difference: 7%
of nicotine e-cigarette users and 6% of nicotine patch users quit."
The Rest of the Story
Dr. Ling has acknowledged that the most reliable evidence on the effectiveness of e-cigarettes comes from a randomized clinical trial. I completely agree. Surveys of the effectiveness of e-cigarettes are plagued by selection bias, as are observational studies of differences in quit rates between e-cigarette users and non-users.
So far we're on the same page. We both agree: we need to look at the randomized controlled trial results to make a judgment on the potential effectiveness of electronic cigarettes. We also agree that there is only one randomized controlled trial that has been conducted. And third, we both agree on the results: the trial showed virtually no difference in the effectiveness of e-cigarettes compared to nicotine patch users.
OK ... so from this clinical trial, we agree that the most reliable evidence to date shows that e-cigarettes are comparable to the nicotine patch in efficacy for smoking cessation.
But from that evidence, Dr. Ling draws an inexplicable, illogical, and unsupported conclusion: E-cigarettes are not effective for smoking cessation and smokers should use NRT rather than e-cigarettes.
But based on the clinical trial, if e-cigarettes are ineffective for smoking cessation, then so is the nicotine patch. As Dr. Ling acknowledged, there was "virtually no difference" in the effectiveness of the two products. Another way of stating this is to say that there was no evidence that the nicotine patch was any more effective than electronic cigarettes. Or, you could state it as follows: electronic cigarettes are just as effective as the nicotine patch for smoking cessation.
No matter how you slice it, the evidence that Dr. Ling presents to support her conclusion that e-cigarettes are not effective actually shows that e-cigarettes are just as effective as the nicotine patch. The quit rates were virtually identical with the two products under randomized conditions. Nevertheless, she concludes from this evidence that e-cigarettes are not effective, while the nicotine patch is effective.
The only explanation I can think of for this faulty reasoning is strong investigator bias. To draw such a conclusion from that evidence suggests that a researcher has reached a pre-determined conclusion and that the existing bias is shaping the conclusions.
Perhaps it is not surprising, then, that this same researcher was involved in what I consider to be dishonest research reporting on the effectiveness of e-cigarettes for smoking cessation.
This is the second example in two days which demonstrates that tobacco control researchers are so biased against e-cigarettes that
they have thrown away the rules of causal inference in order to demonize
these products, which in truth are being used by hundreds of thousands
of people in an attempt to save their lives by quitting smoking.
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