Monthly Archives: March 2017

Editors of Tobacco Control attack blogs: protecting science from cranks, or activism from science?


by Roberto A Sussman

[Editor’s Note: This post is the third here on the recent Tobacco Control editorial. The first two, by me, are here and here, and I plan to cap it off with a fourth next week. This guest post was inspired by a comment Dr. Sussman left on one of the previous posts. His outsider perspective, from physics, offers insight that may not be apparent to those of us mired in social science and health debates, and he provides a deeper dive into the stated policies of the “journal” than anyone else has done. –CVP]

In a recent statement of editorial policy the editors of the journal Tobacco Control declared that the journal’s “Rapid Response” section will be henceforth the only legitimate space to express a scientific critique of articles published by the journal. In particular, the editors singled out (unnamed) internet bloggers as illegitimate critics.

This editorial policy reads as an unnecessarily harsh and defensive reaction, as scientific debate in all fields has never been narrowly confined to peer-reviewed journals, and more so in the current age of broad internet usage and social media. Moderated internet sites (such as the Los Alamos National Laboratory LANL arXiv site) have become a regular and very handy communication channel in physical and mathematical sciences and are fully as serious as journals; researchers can upload material not yet published in a journal (under review), or not intended to be published in a journal, to induce an open discussion of fresh (even controversial or unorthodox) ideas without the constraints of the formal review process. Blogs and Facebook pages exist in all disciplines that serve as useful complementary spaces where research issues can be discussed either informally, or with varying degrees of rigor, mostly involving scientists and graduate students, but also educated non-scientists that may be interested. Besides all these points, publication in peer-reviewed journals is not a guarantee of solid or good quality research, as many peer-reviewed articles in “official” journals report false, methodologically inconsistent, or dishonest results.

However, some forms of “unofficial” critique are neither valuable nor useful. Scientists make an effort to avoid and exclude cranks and crackpots voicing (mostly in social media) all sorts of critical opinions on various scientific topics (especially politically controversial ones). Typically, these characters cleverly juggle (out of context) technical terminology to produce theoretical constructions that may fool lay persons, but are easily seen as incoherent nonsense by any professional researcher (or even a competent undergraduate student). As a common feature they deflect criticism by invoking conspiracies directed by some “scientific establishment” bent on silencing them. As a professional scientist (specialized in theoretical astrophysics and cosmology), I can recall very frustrating experiences involving encounters with this type of non-scientific critics. I have also engaged creationists and “UFO-logists” in front of non-scientific audiences, and have learned the hard way that debating scientific issues requires proper rules of engagement and proper spaces (which does not exclude blogs). Without the appropriate environment and moderation, scientific arguments (even if expressed in non-technical manner) cannot compete with “punchlines” or quick soundbites and analogies.

Medical sciences are not immune to science trolling, as can be witnessed by the efforts of groups like ACSH (American Council of Science and Health) to expose all sorts of doubtful health claims promoted by fad peddlers and cranks writing in social media. This type of science trolling about medical issues has more direct and significant social impact and consequences than in physics. Statements promoting well-being, or warning against terrible ills that would follow automatically from some diet or substance consumption or from adopting a new habit, have an immediate practical impact for those accepting them as true or plausible. We have fallacies potentially producing immediate behavior patterns. By contrast, a cranky statement from physics trolling, such as “a black hole emerging from the Large Hadron Collider (LHC) may cause a great planetary catastrophe”, sounds distant and abstract even to those understanding or believing it. After all, whether one believes it or not, there is no practical course of action to prevent the whole earth from being carved out by a massive black hole, but for those believing that diet X cures cancer, adopting and promoting this diet is concrete and doable. The apparent fallaciousness of such a claim (i.e. diet X does not appear to cure cancer) can only be verified by looking at data-based statistics after decades of observation. It is very unlikely that the lay public will follow up the long-term epidemiological studies. As a consequence, large sections of the public may keep believing fallacious health claims (especially if propagated by wide media coverage) and those propagating it are very likely able to get away with it (especially if well connected politically). On the other hand, cranky predictions from physics trolling tend to be rapidly disproven and forgotten: no planetary catastrophe happened when the LHC started functioning.

While the disinformation propagated by science trolling and the peskiness of some social media crackpots are very disturbing, these phenomena can not serve as reasons to decree a strict enclosure of all scientific discourse and debate within the walls of academic journals. Even if we assume that the editors of Tobacco Control (and other scientists) could be legitimately annoyed by cranky “outsider” critics writing in social media and blogs, their editorial is an evident over-reaction. Normally, scientific journal editors would not bother expressing a forceful editorial policy based on declaring war on this type of science trolling. The latter is simply and unceremoniously filtered out of the scientific debate without constraining the discussion and critique to strict officialdom.

The key issue is to understand what lies behind this overreaction is to ask: Are the bloggers that annoy the Tobacco Control editors part of the legion of social medial cranks that pester scientists in various disciplines? To answer this question we need to examine the material posted by these bloggers. If this material is worthless inconsistent nonsense disguised as technical criticism, then the Tobacco Control editors may have a point (even if they exaggerate). But if this material is valuable and methodologically sound criticism, then the defensive reaction from the editors would likely follow from their inability to disprove them within the rules of scientific debate. To address these questions we also need to understand the specifics of the Tobacco Control journal and the research it publishes, as well as the motivations and backgrounds of the critical bloggers and the material they post.

To the external eye, Tobacco Control looks like an ordinary scientific journal: it has an editorial board of professors; its contributors are PhD’s and other credentialed researchers working (mostly) in academic or government environments, receiving public and industry (pharmaceutical) grants; it undertakes a formal peer-reviewing process; it includes a rapid comments section; etc. This looks like any journal in other disciplines.

However, this resemblance is a deceptive illusion based on common external markings and trappings. Tobacco Control is not a proper scientific research journal that serves a real academic community. It is a journal for a loose alliance of academics and regulators (mostly, physicians, lawyers and other non-scientists) whose main task is to advocate and promote a specific tobacco regulation policy with the aim of eradicating tobacco and nicotine usage.

The advancement of the policy strategy is paramount for the journal and is not open to debate, with the “science” part and related technical aspects in the research it publishes being strictly confined to tactical issues subservient to their potential utility in this advocacy. This characterization requires no secret knowledge. A glance at the recommendations to prospective authors of articles to be published by the journal clearly and openly states its research orientation and strict priority:

The principal concern of Tobacco Control is to provide a forum for research, analysis, commentary, and debate on policies, programmes, and strategies that are likely to further the objectives of a comprehensive tobacco control policy. In papers submitted for review the introduction should indicate why the research reported or issues discussed are important in terms of controlling tobacco use, and the discussion section should include an analysis of how the research reported contributes to tobacco control objectives.

In fact, prospective authors are explicitly discouraged from submitting articles which may contain potentially valuable scientific material but have no direct effect on the advancement of the core policy strategy. From their list of papers they are not interested in:

Papers that show the authors have never opened Tobacco Control and do not understand its primary focus on tobacco control rather than on tobacco and its use and health consequences. We are interested in such papers, but only if their authors address the implications of their findings for tobacco control.

While it may be argued that most research is (or could be) connected to some type of social activism that could have some public policy implications or to other type of social or political “extra-science” concerns, no journal I know of in other disciplines (not even in the politically contentious climate change issue) functions with such a strict focus and dependency on advocacy and a specific political agenda. This renders Tobacco Control primarily an activist broadside that acts as a travesty of a science journal.

To illustrate how the science part of Tobacco Control is just skin coverage to a particular advocacy position, we need to examine what lies beneath this skin. I elaborate below on this issue.

Practically all the published articles in Tobacco Control present research that fully complies and completely agrees with the elements that justify the regulatory agenda that defines the journal. This lack of disagreement on core technical issues signals a sort of inbuilt monolithic alignment that one expects to find among echo chambers of political activists or dogmatic sects, but is quite suspicious and uncommon in all fields of science where dissent on core issues occurs and is voiced (of course, I do not mean crackpot dissent, but dissent within the rules and bounds of scientific activity).

Perhaps editors or contributors of Tobacco Control might argue that this unanimity is justified because the “hard science” behind their strategic policy “has been settled”, and thus disputing the policy would imply a “flat earth attitude” based on questioning well established rock solid scientific research. However, this is a clear fallacy: there is no factual basis in the assumption that health science has fully resolved all tobacco related issues and thus has become cast in stone. There is strong evidence (epidemiological and physiological) on high health risks and hazards from primary cigarette smoking, but many open problems still remain to be researched, and evidence is weak or even contradictory (i.e. science is far from “settled”) on other related issues, such as health risks from environmental tobacco smoke (ETS) or from other tobacco and nicotine delivery products (smokeless tobacco or electronic cigarettes). These issues, especially harm from ETS exposure, remain controversial, and thus must be open to debate. A rigid set of policy recommendations on these issues has questionable scientific basis. The unanimity on core issues proclaimed by the Tobacco Control journal bears much more resemblance to “toeing the party line” in a political or ideological agenda than endorsing science.

Another issue that reveals the skin depth of the scientific part of Tobacco Control is the technical sloppiness (and in some case outright methodologically fatal flaws) of many articles published in the journal. Some might think that it is necessary to be a trained health professional to properly appreciate and evaluate the technical aspects of medical research on tobacco that could justify a regulatory policy. This is not so. While expert analysis of clinical issues and diagnosis and treatment might require medical or health science training, most articles published in Tobacco Control rely on results of epidemiological research that can be well understood (at a core level) by any professional possessing a decent training in statistics and some knowledge of social science methodology. Also, professionals with a decent knowledge of the physics and chemistry of gases and aerosols can similarly evaluate issues related to putative harms from ETS and e-cigarette vapor.

There are many examples of methodologically deficient articles published by Tobacco Control. In particular, I cite two studies published recently that contain fatal flaws:  (i) a 2016 study claiming to have detected a 11% decrease in heart attacks in Sao Paulo, Brazil, immediately after the enactment of a city-wide smoking ban on bars and restaurants and (ii) a study claiming that usage of e-cigarettes is a “gateway” to smoking among high school students in the USA. In both cases the data was handled very sloppily and the results blatantly contradict available evidence. Nevertheless, they got published, which implies that either: (a) the editors and peer reviewers were utterly incompetent, or (b) that technical quality and methodological consistency are secondary concerns when the prospective articles are deemed by the editors to provide a significant contribution to the journal’s main concern: the regulatory agenda. In fact, (a) and (b) above are not necessarily mutually exclusive.

Articles dealing with tobacco/nicotine issues with similar themes and fatal methodological flaws have appeared in other journals. The Sao Paulo study is a sort of sequel to the famous “Helena miracle” study published in the BMJ flagship journal (same publisher as Tobacco Control), which has been widely criticised and debunked (example), whereas the study on teenage vaping fits the pattern of another study published in Lancet Respiratory Medicine, which was also heavily criticised (example). Both of these studies are co-authored by known anti-tobacco activist and prolific contributor to research on ETS and tobacco issues in medical journals, Prof Stanton Glantz (the Truth Initiative Distinguished Professor at The Center for Tobacco Control Research and Education at UCSF). These patterns clearly illustrate the fact that the advancement of the regulatory policy as a paramount concern that even supersedes quality control in methodological consistency, is not confined to the Tobacco Control journal, but extends to the whole cabal formed by the vast majority of public health researchers publishing in journals articles that deal with tobacco issues that may have implications in regulation policies.

It can be argued that technical flaws, such as sloppiness in handling data and statistical hodgepodge to obtain outcomes favouring funders’ preferred conclusions, are not confined to Tobacco Control and similar journals involved in researching tobacco/nicotine issues, but are common drawbacks in other disciplines as well (especially in various branches of health sciences).  However, the credibility of scientific research is undermined even more when, besides these drawbacks, journals (such as Tobacco Control) themselves gauge and evaluate research results by their utility for advocating a specific regulatory policy. Since the latter is endorsed and implemented globally at the highest bureaucratic and government levels, authors of such flawed studies are basically free from scrutiny and are thus more than willing to publish any research that favours their advocacy even if it contains extremely misleading and false results.

Articles that exhibit this type of scandalous level of faulty methodology would never be published in my research area. This does not imply that erroneous or false (or even fraudulent) results are never published by physics journals. But once proven wrong or debunked, the authors and journals acknowledge the faults. Two years ago data the BICEPS2 observations seemed to have found a weak signal providing indirect evidence of tensor modes associated to gravitational waves that could have been produced during cosmic inflation. If verified, this signal would have been the first empiric proof of the inflationary hypothesis and a strong indication for the existence of gravitational waves (thus further corroborating General Relativity theory). However, it turned out that the handling of the BICEPS2 data had been sloppy, that the data was corrupted by Milky Way dust, whose noise completely buried the detected weak signal. In contrast with medical journals refusing to withdraw health claims on tobacco/nicotine related issues that were later debunked, the BICEPS2 claim was immediately withdrawn by all involved researchers and journals.

Now, what about the bloggers that the editors of Tobacco Control wish to excommunicate? Are they science trolls? The social media blogs that criticize articles appearing in the Tobacco Control journal (and similar journals) are quite diverse, with perhaps their single common feature being their opposition to the type of tobacco and e-cigarette regulation that is aggressively advocated by these journals.

Some of the blogs represent the vaping community and some claim to speak for smokers and vapers. Others are more broadly libertarian. Some of them argue the case for the tobacco harm reduction (THR) approach, even intensively promoting vaping or smokeless tobacco as a substitute for cigarette smoking, while others adopt a pragmatic approach that supports THR without campaigning against combustible tobacco. Some of these blogs are scholarly defenders of science. Some are not scholarly, but aim to provide a voice for a community of smokers, smokeless tobacco users, and vapers that actually enjoy using the products and feel personally affected by the social stigma produced by the intrusive bans that follow from the policy recommendations.

These bloggers, as well as most readers commenting on their posts, may be critical but are not on denial of the health risks from smoking, particularly cigarette smoking. As far as I can tell, very few of the bloggers and readers  advocate the return to the old days when smoking was almost unregulated and allowed everywhere. Instead, all  bloggers and readers express a generalised desire for a more humane regulation of tobacco smoking (and now of vaping), with the right of nonsmokers to smoke-free environments being respected, but also demanding that smokers (and vapers) must be  able to enjoy public indoor spaces where they can smoke/vape without being shamed and vilified by “denormalization” policies. Bloggers and readers comment how such policies are promoted by a global conjunction of increasingly authoritarian public health lobbies and charities, whose aims are perceived to lie far from a genuine public health concern, and are more about the preservation of their bureaucratic power (the “gravy train”), with many of them having intimate financial ties with the pharmaceutical industry.

Some of the blogs are quite scholarly (some are run by experienced scientists) and do provide, together with useful verifiable information, a solid reasoned criticism of the loose methodology prevalent in the research published in Tobacco Control and other health journals. In fact, all the methodological flaws I mentioned before, the faulty meta-analysis — the statistic hodgepodge, the “Helena miracle” claims, the mishandling of the data, the simplistic “addiction” theory, the dismissal of previous results not aligning with the agenda — have been extensively and rigorously discussed in the pages of these scholarly blogs. While most blogs (even the scholarly ones) tend to avoid the dry cauterised style full of technical terms found in published journals, favoring a more colloquial, but well-articulated style amenable for an open and broad audience, a lot of the material appearing in the scholarly blogs could easily meet (after some editing and style changes) the methodological standard of quality that merits publication in a scientific journal.

These scholarly bloggers actually provide a very fresh and healthy counterbalance to the “official” tobacco/nicotine research published in academic research, which is excessively constrained by global public health politics and by the vested interests of the pharmaceutical industry. In particular, they promote varied proposals of a new regulatory paradigm based on THR to replace the policies trying to enforce the “abstinence only” approach. While the bloggers are certainly not beyond criticism (and some may tend to become too self-centered and too defensive), they are absolutely not (not even remotely) comparable to crackpots or science trolls. In fact, these bloggers provide the necessary and refreshing debate and exchange of ideas that could prevent the science on tobacco/nicotine issues from becoming practically indistinguishable from quasi-religious dogma.

Controversy on core issues and the challenging of dominant paradigms occur naturally  in every scientific discipline: there is no reason why this should not occur in public health science. In fact, part of the community of public health scientists has resonated with the criticism expressed by the scholarly bloggers, agreeing (with various degrees of consistency and conviction) with them on various proposals for shifting regulatory policies towards a THR approach. To claim (as a lot of official tobacco scientists do) that all this wide spectrum of voices criticising the dominant politics are mere fronts of the maligned tobacco industry is a ridiculous libel that can easily be disproved.

It is clear beyond doubt that the harsh defensive reaction of the editors of the Tobacco Control journal stems from their inability to acknowledge serious technical errors that the bloggers they would like to excommunicate have spotted. These editors are exploiting the fact that, externally, their niche (a journal whose editors and contributors are credentialed academics) resembles the niche of other scientific journals, while the bloggers (even if posting valuable material) are outside these “official” channels. The hope of the Tobacco Control editors is to secure, by association, the professional authority of journals in other sciences and that this will help them to deflect the bloggers’ criticism.

The tactic of the editors of the Tobacco Control journal is then evident: to identify all their critics, but especially those writing in scholarly blogs, with the social media crackpots that besiege scientists in other disciplines. Their editorial is an attempt to utilize their external resemblance to a real research journal, serving real academic communities, for this purpose. Their target audiences are: first, the media, the politicians and the medical community who can implement the policies they advocate; second, the public health authorities and other academic communities (which would identify with them because of the superficial resemblance); and third, the lay people, who are completely unaware of the inner workings of scientific activity and simply assume that somebody like Prof Stanton Glantz, a co-author of the fraudulent “Helena miracle” (to use a well-known example), is as good a scientist as any other.

It goes without saying that the dominant majority of public health researchers involved in tobacco/nicotine research are acting with gross dishonesty when they paint themselves as bona fide scientists besieged by social media cranks or “Big Tobacco” front. Neither Prof Glantz nor any other prominent individual in this cabal has ever disavowed the most extreme pieces of tobacco junk science published in journals — for example, the claim that minutes of outdoor exposure to ETS produce coronary disease, or the existence of “third hand smoke” (health harms somehow resulting  from tobacco smoke residue in rugs and walls where someone smoked). The claims from such pieces of published third-rate junk science are at the same level of science trolling as the writings of cranks in social media. There is little difference between the “third hand smoke” claim, which treats tobacco smoke as a sort of quasi-magical substance that is lethal even in extremely minute dosage, and quasi-witchcraft statements by a social media freak naturist sect announcing that wearing a pyramidal magnetic amulet around the neck protects from cancer. Yet the naturist sects do not claim patronage from science, whereas this type of officially published ultra-junk science does. For this reason, the latter is much more harmful socially than the former.  

The identification of Tobacco Control critics with crackpots besieging scientists may backfire, as it can easily be shown to be false simply by reading through the pages of the scholarly blogs and comparing with the pages of the journal that they criticize. Not even the non-scholarly blogs and their readers can be tagged as trolls, as (in general) they avoid the extreme abuse seen among social media trolls. In fact, anybody having tried to debate extreme or neurotic anti-smokers (whether laypersons or physicians) rapidly discovers that expressing any doubt or nuance on the usual soundbites, such as “second hand smoking kills” or “you have no right to force your filthy habit on me”, or various forms of “protect the children” demagogy, is met by ad hominem, angry denials and abusive language. A large minority of anti-smokers in all walks of life are very prejudiced individuals whose attitudes to smokers are no different from attitudes of racists and homophobes towards their hate targets. In fact, anonymous anti-smokers in social media exhibit all the unpleasant features of internet trolls and crackpots: dogmatic belief in possessing absolute truths together with invoking conspiracies (the tobacco industry luring “kids” to become nicotine addicts). Unfortunately, some academics that publish on tobacco issues in official journals espouse the same type of cranky troll-level ideas, just expressed in polite technical terms.

Evidently, the editors of the Tobacco Control journal are trying to mobilise the medical-political bureaucracy and charities that share their anti-tobacco/anti-nicotine advocacy. The aim attached to their recent editorial is to pin all its critics (especially scholarly blogs) with the crackpot label, as the old “tobacco industry mole” label is no longer credible. They may succeed, but nevertheless, the label is deceptive. Sooner or later most people will realise it and admit that “the king is naked”.

Teen vaping and gateway effects (Lee Johnson article and interview with me)

by Carl V Phillips

Lee Johnson has two good posts about teenage vaping, with an emphasis on claims that it is a “gateway” to smoking. The first looks at how to scientifically assess whether there is a gateway effect, and the second is mostly about policies that might discourage teen vaping. They are long, but you should read them if you are interested in really understanding the science and politics of vaping (as opposed to those who read blogs like they use Facebook, seeking a minute of reading to affirm their personal biases; since you are here, presumably that is not you).

Lee interviewed me (via email) for the article. We agreed that I would post the full text of my interview here after his story came out. It turns out to be largely redundant with his article because he did such a good job of capturing what I said. The interview follows (his questions in italics), and after that are a few notes I had on the article (TL;DR version of that: When reading Lee’s article, skip over the quotes from Michael Siegel, because they are mostly wrong).

Oh, and the TL;DR version of Lee’s analysis of the gateway effect is summed up by his points:

[W]e can make a very strong argument that the vaping-to-smoking gateway effect is unlikely to be a significant problem. But, as much as we might like to, we’re not in the position to completely discount the possibility either.


[T]he reason we don’t have the studies to answer the question appears to be because few people really even care about the reality of the gateway effect. People opposed to vaping want something vaguely resembling science to point to in support of their rhetoric, and we vapers want something to point at to shut them up. The science doesn’t need to be robust for that, so why go to the effort?

The interview:

How would you describe the Surgeon General’s treatment of the evidence when it comes to youth vaping?

Faux credulous.

That is, the authors pretended to believe basically any bit of (what they would consider) bad news that was asserted by anyone. I say “pretended” and “faux” because, while they are not exactly serious scientists, it seems unlikely the authors are really are so dim as to believe all that. This is reinforced by the fact that they did not seem to believe any of the analysis that disputes those claims.

This is standard and predictable for “official” reports (in this field and most others): A political actor decides what the message is going to be, based on political goals, and then commissions a report that is designed to support the thesis. The authors may have a bit of independence, but are rarely at liberty to contradict the chosen message and, in any case, are selected because they have already demonstrated they endorse the politically-motivated conclusions. This applies equally to the official reports where a different decision was made about what the conclusions will be, like the PHE and RCP reports.

Official reports are heavily used by activists on both sides of the fight because other political actors like the work of political actors, but anyone actually seeking the truth should avoid them. (As an aside, it is, of course, the case that the pro-vaping official reports are more scientifically accurate than the anti-vaping ones, but that is because deciding to support the pro-THR position causes one to be closer to the truth, not the other way around. That is, the decision about what the report would say happened to be closer to scientifically accurate; the decision was almost certainly not made because it was scientifically accurate.)

What do you think about the decision to focus the report on youth vaping and almost completely ignore the issue of vaping’s risks relative to smoking?

Anti-tobacco efforts have not been about the actual risks for longer than e-cigarettes have been a thing. To the anti-tobacco extremists who control most of the discourse on the topic, a low-risk tobacco product is a problem, not an improvement. Tobacco controllers prefer high-risk products because people have a compelling reason to not use them. If the products are low-risk and people know that, they have little reason to avoid them. I have written more about this in my series on why there is anti-THR.

Your paper on the evidence cited for gateway effects gives a clear run-down of the issues with the evidence used to support the gateway hypothesis. My impression from reading it is that none of the currently available evidence is sufficient to answer the question one way or another – is that a fair conclusion to draw?

You actually have to step it back a bit and ask “what question?” If the hypothesis is “there has been one gateway case ever”, let alone “there will be a gateway case eventually”, then the answer is undoubtedly “yes”, and no evidence is really needed. There are enough exposed at-risk individuals (i.e., those who could become a gateway case and who try vaping) that this falls into the “if it is not impossible then it is inevitable” zone.

This is in spite of the fact that we should not expect this gateway effect to happen much, for reasons I go into in the paper. Gateway proponents have tricked everyone, including their critics, into not questioning the underlying premise that it is reasonable to expect vaping to often cause smoking. In reality it seems rather unlikely. While this is a little more plausible than the original “cannabis use causes opioid/cocaine/etc. use” version of the gateway claim, it still makes only a tiny bit more sense than claiming that vaping causes risky sexual behavior.

By contrast, if the hypothesis is “vaping causes everyone who does it to start smoking within a week” then it is pretty easy to disprove with available evidence. If it is “vaping causes many people to become smokers ten years later”, then there it is difficult to imagine any possible evidence that could inform it. I trust you see my point.

So we have to start by specifying what seems to be a reasonable version of the claim We have to do it since the proponents of the claim never actually define what they are claiming. It seems reasonable to go with something like “regular vaping causes 10% of the would-be nonsmokers who do it to become smokers within two years.” Then your conclusion is right: It is theoretically possible to assess this scientifically, but no evidence we actually have should move our prior belief about whether that is true by very much.

What would you say are the biggest issues with the studies we have so far?

The second biggest issue is the one I just alluded to: No one making gateway claims ever specifies what they are actually claiming, in terms of what portion of would-be nonsmoking vapers are caused to be smokers, over what period of time, etc. This is not necessarily a fault with a study itself (unless it was specifically designed to look for a gateway effect, in which case failing to properly define the effect is a fatal flaw in the study). But it is a fatal flaw in any attempt to interpret the study (either as supporting the gateway claim or arguing against it). An analysis that provides good evidence that vaping does not cause 50% of would-be nonsmokers to take up smoking might still support the claim that it causes 10% to do so (or, more likely, provide no useful information about the latter claim).

It is not interesting to claim that there is any gateway effect, just like it is not interesting to claim that an exposure causes any cancers. Epidemiology is a science of measurement, not of detecting the dichotomies that are sometimes interesting in physics or paleontology. A casual reader of epidemiology (a category that includes most epidemiology researchers!) would be forgiven for not realizing this, given how results are often described dichotomously. But magnitude is what matters. Consider the claim “vaping causes cancer, specifically exactly one cancer death ever.” This is more similar — in terms of the science and decision-making — to “vaping is harmless” than it is to “vaping increases cancer risk by 50%”. The same goes for the gateway claim.

On top of that, there is the question of what population is being considered. There are no constants in epidemiology. Any decent Epid 101 class teaches that who, when, and where matter. Vaping might have trivial gateway effects in a population where smoking is relatively normal and easily accessible, but rather larger effects in a hypothetical future populations where vaping is normal and smoking is something very few kids ever consider trying.

The biggest issue is the (often intentional) failure to address the epidemiologic concept of response types. I am working on a paper right now that focuses on this. Basically for dichotomous exposures and outcomes, as with the typical gateway claim, there are four response types: immune (will not have the outcome regardless of the exposure), doomed (will have the outcome regardless), protective (will have the outcome if not exposed, but will not have it if exposed), and causal (will have the outcome if exposed, but not otherwise). A gateway case is properly defined as anyone of the causal type who is exposed.

The unknown proportions of doomed and immune types, in particular the different mix in the exposed and unexposed populations (known as confounding), means that most statistics cited as suggesting a gateway effect offer no such evidence. That is, we can be sure there is an excess of doomed-to-smoke types among vapers (as compared to never-vapers), and there is little doubt that this disparity dwarfs any actual gateway effect. Thus, if response type is not thoroughly measured or controlled for (and it never is), it is simply not possible to detect the gateway effect. Any association between the exposure and the outcome is plausibly explained by confounding; since there is no estimate of how much confounding there is, it is impossible to know if the association represents any causal relationship above and beyond the confounding.

Cutting the other way, if there are any protective types in the population (and there undoubtedly are), that will mask any gateway effect. So if there were no confounding, the association would be a measure of the net of causal types minus protective types. If there is a sufficient proportion of protective types, it would mean the net effect of vaping is to reduce smoking in the particular population. But this does not mean there is not also a gateway effect (i.e., there could still be some exposed causal types).

Anyone who does not understand the previous three paragraphs has little hope of making sense of the evidence about gateway effects. Any real expert on the topic would be able to write those three paragraphs if prompted, something very few of those claiming expertise could do.

What would be required to conclusively answer the question of whether vaping is a gateway to smoking?

Well, “conclusively” might be a bit much to ask, unless the question is one of the extreme versions I have suggested. But as I lay out my previous paper, the best chances of measuring the effects lies in either natural experiments or really good propensity scores.

An example of a natural experiment would be to take advantage of vaping being a fad among teenagers that has (or at least had) very uneven uptake. If someone were to identify high schools with high vaping rates and match them to demographically very similar schools with low rates, and then compare smoking rates, we could estimate the net effect (causal cases minus protective cases). That would not exactly measure the gateway effect because of that problem I just explained. But it would offer a measure of the net of causal minus protective types in the exposed population and this net seems to be what most political debates focus on (though a deeper dive into the moral philosophy suggests that saying protective and causal cases just cancel each other out is not an easily defensible position).

A propensity-score based approach would be to create the best available estimator of whether someone is destined to smoke (asking lots of questions about preferences, behaviors, and exposures) that is independent of vaping exposure, and then see if vaping exposure is associated with smoking among many who otherwise appear destined to not smoke. Since no propensity score is perfect, this would probably require some fairly sophisticated statistics as well as a serious stepwise approach.

I realize that is fairly opaque. Which is the real point: Using propensity measures or tracking natural experiments would require a lot more work than the standard practice of throwing together a half-assed survey about behaviors and a few demographic questions, and administering it to a convenient population. It would require skills that few who study tobacco use have. It would also require serious scientific honesty, because it is trivially easy to pretend to be seeking the truth using methods like that, but really just be dressing up a politically determined conclusion.

Why do you think that research hasn’t been completed?

That has answers at several levels. First, we are talking about public health research here, where there is basically no incentive to do decent science. The rewards (employment, funding, news coverage) are the same for doing a simplistic junk science study as for putting in the effort to do a complicated genuinely truth-seeking study. It is no more difficult to publish junk than it is to publish good work in public health. Indeed, it might be easier. Furthermore, most of the people doing this work do not even have the capability to figure out how to do things right. We are talking about people who have never once in their careers properly piloted a survey, reported a meaningful sensitivity analysis of their model, or consulted an expert before just charging in to concoct an ad hoc research project. They are less likely to figure out an innovative and careful way to answer a tough question than kids doing a high school science project.

Second, the anti-tobacco researchers are worse than average, in terms of scientific skills, even compared to the low standards of public health. Moreover, they know they can get anything published and into the news (which is how they really earn their pay) if it has the right conclusions, regardless of how absurd their analysis is.

Third, for this particular area of research, pretty much no one actually cares about seeking the truth. Anti-tobacco activists want to say there is a gateway effect, to denigrate e-cigarettes. Pro-ecig activists want to say there is no substantial gateway effect, to fight back. (That was being charitable, by the way; the typical claim is that there is no gateway effect, which is absurd.) Both groups cite statistics that, for the most part, do not support their claim at all. This is a rare area of the tobacco wars where critics of tobacco control are almost as unscientific as the tobacco controllers.

I suggested in my recent year-end post that the debate around e-cigarettes (like the debate about other tobacco products) has substantially entered a post-truth era: the rhetoric in the fight is largely unconstrained by science, and the “research” is just designed to produce rhetoric. It is actually not that bad for the technology research, where industry researchers seek the truth to try to figure out how to make or use the products better (in particular, less harmful), and to honestly assess the risk. But the gateway issue is totally post-truth. No one in that particular fight is interested in the truth, just the message. Finding out the truth might be inconvenient.

If someone does become curious about the truth, they probably quickly figure out that the necessary research is not worth the effort. We can be confident there is nonzero gateway effect, but also that the magnitude must be small enough that it will be lost in the noise. That is, given the problems I discussed in the context of response types, is hard to imagine that any plausible research could measure what is undoubtedly (for reasons I explain in my paper) a very small gateway effect precisely enough to distinguish it from zero or from double the actual rate. So it is not really worth doing. Of course, those who wish to argue there is no large gateway effect could do the legitimate research, because it would undoubtedly reinforce their message. But since they are content to cite research that does not actually support their claim, and get away with that just fine, why would they bother?

In the US, it seems that the potential risks of vaping are put front and center, while the very real benefits are rarely mentioned. Do you think that the desire to discourage youth vaping is to blame (at least partially) for this bias?

No doubt pursuit of that goal makes the disinformation somewhat worse. But I suspect it would not be much different even if that were not an issue. Tobacco controllers want to discourage all tobacco product use, regardless of its benefits, and they control almost all the money and media in this space. Even if kids were magically prevented from ever vaping, the disinformation campaigns and attacks on adults’ liberty would still exist.

Is there an inherent conflict between discouraging non-smoking teens from vaping and encouraging adult smokers to switch, or is there a way to do both?

It is an inherent conflict. It is simple economics. If we increase the net quality of the products (better devices, attractive flavors, affordable prices) or the perceived quality by increasing people’s knowledge (knowing it is low-risk), it makes it more attractive for everyone. If we lower the net quality or hide information it is going to make it less attractive for everyone.

Of course, if there were a way to make the products differentially appealing, that could create a wedge between these (though this would not be sufficient to say it should be done). So, for example, if the myth that particular flavors are more appealing to teens were true, that would offer ways to drive a small wedge. But there is not even a small wedge apparent to those of us in the reality-based world, let alone a big one. It turns out that teenagers are remarkably similar to people.

What, if any, actions do you think should be taken to discourage non-smoking teens from vaping?

That, of course, is an ethical question, not a scientific one. Every political discussion is predicated on the assumption they should be discouraged from vaping. This is far from self-evident, but no serious analysis of the question ever takes place. The most obvious argument against the assumption is that there are enough protective types among teenagers that the resulting reduction in smoking initiation will outweigh any downsides. A bolder, but still prima facie legitimate, argument is that it is not obvious there are sufficient downsides of the behavior to warrant any actions, at least not beyond just banning sales to minors. Bolder still is the argument that the benefits of nicotine for a subset of teenagers are quite large, and they should be using it (note the explosion in the use of nasty prescription stimulants over the period where teenage smoking decreased). Oh, and your question implies the assumption that smoking teens should not be discouraged, which also does not go without saying. Obviously a lot of people seem to feel otherwise (though they rarely even attempt to articulate a normative argument for their position).

My point here is not to endorse or dispute any of those possible positions, but to note that there is no serious discussion of what the basis for that “should” should even be.

One thing that is clear is that, at worst, teenage vaping is just one of hundreds of little things that kids might think are a good idea but their elders might realize are not. It is hard to imagine any knowledgeable parents being nearly as worried about their kids vaping as about them driving dangerously, getting pressured into ill-advised sex, drinking, not trying in school, smoking weed, not exercising, and numerous other hazards of adolescence. Actual vaping (as opposed to just trying an e-cigarette a few times) is also far less common that those more serious hazards. The breathless swooning about teenage vaping, which is responsible for the concocting of gateway claims, is all a product of a small group of anti-tobacco fanatics who consider it a moral affront that anyone (adult or teenager) uses the products.

It is no different from those who take moral offense at gay people or women not covering their heads in public. The “problem” is considered much of a problem only because some people chose to declare it a problem. Unfortunately, modern Western liberalism has a habit of insisting we “respect” people’s choices, even when those choices are to try to restrict others’ behavior. So the fanatics are given the benefit of the doubt instead of being told (like you would tell any child who is trying to impose his preferences on others) “your dislike of this is your problem, not ours.” Vaping advocates would be wise to stop conceding almost all the fanatics’ claims and assumptions and then try to fight within the tiny space they have left themselves.

My notes on Lee’s article:

The major problem with the article was presenting the analysis from Michael Siegel as if it were scientifically valid. Siegel is a dedicated and energetic supporter of vaping (though not of THR), and very likely offers value to the cause, but his attempts at scientific analysis are very frequently out-and-out wrong. He got his start writing about tobacco control’s environmental tobacco smoke myths and calling out their whole-cloth claims, and he is on solid ground when he sticks to that. Now I usually just avoid reading him to avoid the urge to grade his work, but this forced it in front of me.

I know this is harsh, but after a decade of trying to help Siegel get things right (and to not write about what he does not understand, and to spend more time reading rather than writing so he could see what he does not understand) I have reached the conclusion that it is not going to happen. Certainly nothing short of saying this will get his attention. (I kid myself with that: he is not likely to read this. If he read what I wrote he would avoid many of his errors.) So the only reasonable course of action seems to be to discourage others from thinking he is a good source of scientific analysis, whatever other contributions he might make. What he writes sounds sciencey, of course, which is why people who want to believe his conclusions are often fooled into accepting his analysis, and why it offers useful propaganda value. It is the same phenomenon with Glantz and the partisans who want to believe him. (That comparison is not random, by the way: Siegel apprenticed his science (such as it is) with Glantz.) But the present exercise was truth-seeking, not propaganda.

Most of Siegel’s errors in Lee’s piece should be immediately evident to anyone who reads my analysis. For example, he claims (yet again) that “smoking rates have continued to plummet. This is not consistent with the hypothesis that vaping is a gateway to smoking.” If you read my paper, this post, or just Lee’s excerpts from my interview, it will be obvious why that is wrong. (In fairness to Lee, he was following the accepted role of the reporter, recounting the results of multiple interviews despite the fact one shows the other is wrong.)

Oh, and the first quote from Siegel is him banging on, yet again, about how e-cigarettes are Not Tobacco!!!, claiming this is the main reason why the Surgeon General’s report on teen vaping was wrong. Even setting aside the fact that he is clearly wrong to call this wrong, his obsession with this argument has reached the point of seeming deranged. (There are lots of ways to categorize things, based on different criteria for different purposes. A choice of how to categorize, therefore, cannot be wrong unless it is absurd, like calling e-cigarettes a kind of suspension bridge. Obviously it is not absurd to categorize e-cigarettes based on their role in society and active ingredient, even ignoring the fact that they do, in fact, contain part of the tobacco plant.) At best, this comes across like a six-year-old who just learned that tomatoes are a fruit when categorized anatomically, and smugly telling his parents he cannot finish his vegetables because he only has fruit left.

In fairness, this is not childish smugness and probably not derangement, but rather it is politics-as-therapy (a phenomenon that rarely produces good outcomes). That is, his self-image is as a tobacco controller, and so he cannot come to grips with the fact that his primary public identity is as a cheerleader for something that most people (quite reasonably) call a tobacco product. So he wants to change reality to deal with his personal conflict.

Anyway, moving on…. One point that I did not make in my interview (though it is in my paper), is the observation that being a never-smoker is not a necessary condition for being a gateway case, as is implied in the article and frequently implied or stated elsewhere. Someone who smoked a few cigarettes, or even a lot, might still be a causal type — someone who is destined to be a nonsmoker in the absence of vaping, but destined to become a smoker if she takes up vaping. Indeed, it is not even clear that someone who has already smoked some is less likely to be a gateway case than someone who has never smoked. Yes, the previous smoking suggests she is more likely to have been doomed to smoke. But it also suggests she is more likely to be on the cusp of being a smoker or becoming abstinent, increasing the chance that an exposure like vaping is enough to keep her from becoming abstinent.

Thus, all the analyses that assume only never-smokers can be gateway cases — and thus insist there cannot be many gateway cases because there are relatively few never-smoking vapers — are wrong. Indeed (and this may be the first time I have published this observation), given that there are so many more ever-smoking teenagers who vape or trial an e-cigarette, ignoring the ever-smokers means ignoring most of the at-risk individuals (i.e., potential gateway cases). Someone seeking to deny the gateway claim might gerrymander their definition of “gateway” (which is not a well-defined scientific term) to require that the vaping cause someone to smoke their first cigarette, but this is clearly not what is meant when concern is expressed about the claim. Of course, it is worth reiterating that there is no reason to believe there are many gateway cases at all, but if the goal is estimate the effect then obviously we should not be looking only at the pristine tip of the iceberg.

Finally, a point about that question of whether there is an inherent conflict between encouraging adult smokers to switch and discouraging nonsmoking teenagers from vaping (setting aside the debatable — but never actually analyzed — question of whether there even should be aggressive interventions to do the latter). My point is that apart from the trivial expedient of forbidding sales to minors, along with the horrible option of making possession or use status offenses, there is no apparent action that affects teenagers that does not affect adults in the same direction (though the magnitude may differ). Lee characterized the answer to the question as “a matter of perspective”, but sorry, no — this is a matter of science.

There is no theoretical reason that there could not be some other ways to affect teenagers without affecting adult smokers, but the reality is that none exist. Consider the options that are addressed in the article. After declaring there is no inherent conflict, Siegel offers only sales bans and “marketing restrictions” as methods. It is standard tobacco control rhetoric to claim that there is a well-defined activity called “marketing to children”, that can be restricted. But to anyone in the real world, this is obvious nonsense. Marketing to 35-year-olds cannot be done without also marketing to 16-year-olds. As I noted, teenagers are a lot like people. Any restriction on “marketing to children” beyond banning advertising on the Disney Junior network will also constrain marketing to adult smokers. In fact, I picked that example because Disney Junior is probably the network I watch the most, so even that restriction would reduce outreach to adults. Again, there might be differences in magnitude, but not in sign.

Of course, the savvy tobacco controllers probably realize this is nonsense (though their useful idiots believe it) and know they are just using it as an excuse to ban all marketing, signage, and visibility, and to thereby create stigma. Needless to say, eliminating all marketing that children see (“verify you are 21 by entering your credit card information and scanning your driver’s licence so we can show you our ad”) is eliminating marketing.

Another policy addressed in the article that would not have the claimed differential effect is punitive taxation. The myth here (stated in the article) is that adult smokers are less price sensitive than teen trialers. But this is largely nonsense also. There are exceptions — one appears in the article — of adult smokers who will pay a lot extra for something that helps them quit smoking. Some buy ridiculously priced NRT, after all. But for everyone else, the price of e-cigarettes is a huge potential incentive or disincentive. The same concept applies to punitive taxes on cigarettes: It is a myth that teenagers care more about price. The reality is that for the vast majority of families with Western levels of wealth, kids are more willing and able to spend freely on such things than their parents.

Adults with $20 in their pocket think “I can take the kids for pizza on Friday” or “I can pay off some of my credit card debt”, while teenagers with $20 think “what entertainment can I buy for this? Today.” This is even more true for raising the price of e-cigarettes than it is for discouraging smoking with punitive taxes. An adult smoker assessing the price difference thinks “I will pay (or save) this much from switching, which adds up to X every year”, while a teenager wanting to try something today will not even notice a dollar difference in the purchase price. The difference in response to price that the tobacco controllers think is adult-vs.-teenager is actually “reasonably wealthy person” vs. “impoverished person”. Of course, public health people assume for themselves an in loco parentis attitude toward poor people, treating them like teenagers (part of the reason such people voted to let Paul Ryan take away their medical care, because they are so angry at the paternalistic elites — but that is another story). But that does not actually mean that the people they treat like children are the actual children.

The final example given is the standard myth about flavors. If there really were a group of flavors whose existence causes some teenagers to vape (a dubious claim in the first place) but that causes no adult smokers to switch (or stay switched), they could be banned without affecting incentives for adult smokers. If there really were flavors that had more effect on teenager choices, then they could be banned to have more effect on teenagers than on adults, but there would still be a reduction in appeal to some adults. (Side note: Notice that the conditions are the very strong claim that the flavors’ existence causes vaping or switching, not merely that they have differential appeal.) Again, those of us in the reality based world know there are no such flavors apparent. But the real point is my original one: Anything that lowers the quality will affect the appeal to both teenagers and adults, in the same direction, even if it were one of these mythical reductions in quality that affects teenagers a lot more than adults.

Inherent. Conflict.

Ok, done. This is already too long, so no conclusion statements.

Detecting bullshit in claims about comparative risks across tobacco products

I interrupt  the posts about the Tobacco Control editorial (I expect two more) to respond to a query from a reporter (who, I should note, writes good stuff about THR), who I criticized on Twitter for repeating the nonsense claim that smokeless tobacco is 10% as harmful as smoking in a recent article. He, quite reasonably, asked if I could hook him up with better information. I said that is not so easy (not Twitter-level easy, for sure), and that I would instead write a post for him.

It turns out that the best easy information I can offer is summarized in this passage from my IEA White Paper, Understanding the basic economics of tobacco harm reduction:

The only low-risk [tobacco] product for which we have useful epidemiology, smokeless tobacco, causes only about 1/100th the disease risk from smoking, based on the only existing attempt to calculate an evidence-based estimate of overall comparative risks (Phillips et al. 2006), and calculations for specific diseases support that estimate (e.g., Lee and Hamling 2009). Estimates for other products must be based on what we know about smokeless tobacco, but since there are no reasons to believe they differ much, this is adequate. There is no affirmative evidence that the risks are different.(4) This estimate of harms ignores the apparent health benefits of nicotine consumption (e.g., protection against neurodegenerative diseases), so it is plausible that the net effects are actually positive. Thus it cannot be claimed with confidence that use of [low-risk tobacco] products is less healthy than abstinence.

Footnote 4 reads:

4. A popular claim at the time of this writing is that e-cigarettes are merely 95% less harmful as smoking – i.e., pose five times the gross disease risk of smokeless tobacco – but this is not supported by any evidence.

Later I tweeted this in response to my original comment about the article:


False claim: ecigs 5% as harmful as cigs
False claim: ST more harmful than ecigs
ST 10% as harmful

I really think that is the story. Pro-ecig tobacco controllers have made up the claim that e-cigarettes are 5% as harmful as smoking. I have called bullshit on this claim, as well as the various attempts to finesse it and defend it quite a few times on this page (example). Some e-cigarette advocates are convinced smokeless tobacco must be more harmful than e-cigarettes because… um? well… because those always-trustworthy tobacco controllers told them it was harmful. And they think this is plausible because… um? well… because it contains identifiable bits of the original plant rather than an extract, so it must be worse. Just like chewing coca leaf is worse than smoking crack and apple juice is more healthy than whole apples. (Note: just in case it is not common knowledge, neither of those is true.) As I have noted on this page, if forced to bet on which of the two fairly benign consumption choices is a little bit worse for you, the smart money is clearly on e-cigarettes being less healthy than smokeless tobacco, though we will probably never know with much confidence.

Oh, and the choice of 10% as the result of this “logic” of falsehoods is simply digit preference. No one would say 6%.

Actually there is a really good reason no one would say 6%: It does imply more precision than 10%, and it might cause the reader to start asking questions. Like, “how did you calculate that?” or “what diseases are caused that add up to 6%?” No use calling attention when the answer to those would be “I did not calculate anything” and “hell if I know — I just made that number up.”

I do not know who made up the number that was then repeated in the article (the reporter presumably did not pull it from thin air himself). Maybe it was stated or could be inferred between the lines in the article. Presumably there is some commentary in a journal out there that asserts it. But I am not going to check because I would just as soon not know. There is little to be gained by focusing my disgust on one particular author.

Oh, and if you did not hear the sneer when you read my use of the word “commentary” there, circle back and add it. Because in case it is not obvious, this is a scientific question that should be answered using scientific methods. Opinion pieces do not inform about scientific estimates. (In public health, they also seldom produce informative opinions, but that is another story.)

A claim about risk needs to be risk of something, some particular diseases. So what disease risks from smokeless tobacco add up to 10% of the risk from smoking? It is obvious the claim is bullshit if you understand the research on the possible health risks, and thus know that the worst-plausible-case scenarios, summed up across all diseases, could not add up to close to 10%. Not even 5%. But even if you do not know that, it should be clear that the risk must be the sum of risks for particular diseases. There is no such thing as “just risk”. So if whoever is making the claim does not even specify what diseases are being caused, it is obviously bullshit. Of course the next step must be to justify the quantitative claims — using epidemiology if at all possible.

Another scientific approach is to divide the exposure into understandable component exposures. This is the approach necessary for assessing e-cigarettes, since there is no useful epidemiology (and probably will never be for the current techs). So we have nicotine (close to harmless or maybe beneficial), the carrier chemicals (seemingly harmless at doses that have been studied, though vaping doses are in largely unstudied territory higher than that), and the various flavoring chemicals and pyrolysis products (in doses that are trivial compared to what is considered sufficient to create a health concern). This is the scientific approach taken by the serious effort to make the assessment by Burstyn. The claims of 5% are not serious or scientific.

Here is another clue about bullshit: The comparison to smoking can only be an additional step, after already figuring out the absolute risk. Anyone who has skipped the step of estimating the absolute risk, using some method other than just making up numbers, is trafficking in bullshit. Consider what it would take to figure out the risk from e-cigarettes as a percentage of the risk from mountain climbing. You can look up estimates of the latter’s absolute risk, but then you need to somehow estimate the former, and calculate a comparative statistic. There is no magical way to just figure out the percentage. It is no different if the comparator is smoking. It is obvious nonsense to say “hmm, e-cigarettes seem to me to be 5% like smoking and 95% unlike smoking, so they must be 5% as harmful.” It is no more valid than saying “hmm, mountain climbing is really dangerous and using smokeless tobacco seems a lot less so, so let’s just say vaping is 10% as harmful as mountain climbing”. I trust it is clear that this would be anti-scientific nonsense. It is no less nonsense to do that for smoking.

Vaping and smokeless use have a bit more in common with smoking than they do with mountain climbing, but not a whole lot more. It is not unreasonable to say that reducing your vaping or smoking by half probably reduces your risk (whatever that is) by about half. In that case, we are talking about two very similar exposures (using the same product) and a meaningful quantitative difference in exposure. That estimate actually turns out to be too optimistic for smoking and to be ambiguous (half of what?) for vaping, but it is still a reasonable rough estimate. But you cannot do the same across completely different exposures. I am not sure if I can communicate just how baffling it is, to anyone who actually understands epidemiology, that anyone would think otherwise.

To sum up, to estimate the comparative risk requires first estimating the absolute risk. That estimate requires estimating the risks for particular identified diseases. This is true whether the goal is to create a point estimate or bounds. That is, it is just as necessary to do this to justify a claim that “vaping is more than 95% less harmful than smoking” as it is to justify the claim “vaping is 95% less harmful than smoking”. You would deal differently with uncertainty when doing one rather than the other, but the necessary basic calculations are the same.

Readers of this blog are justifiably incensed with “public health” people just making up pseudo-scientific claims to further their anti-THR political agenda. But these comparative risk claims you see from self-styled THR advocates (who really do not support THR, but that is another story) are every bit as much pseudo-scientific bullshit. It is really hard for those of us who expect scientific claims to be based on scientific analysis to see much difference, in terms of their honesty and relationship with real science, between the two groups.