According to ANR:
"When handed a tobacco-related study - particularly if it claims that going smokefree hurts business - consider these factors to determine if it is a legitimate study or one funded and created by the tobacco industry. ...
Are sales figures analyzed for at least one year?
To identify underlying trends and fluctuations in the restaurant business cycle's yearly sales, was the study conducted over a sufficiently lengthy period to make the data meaningful? Economic impact studies should include restaurant sales data for several years before a law is enacted, as well as for all quarters after enactment. The economy changes for many reasons: inflation, seasonal variation, and fluctuations due to the weather and other superfluous events. Short-term observations cannot accurately evaluate economic impact. By collecting data for several years, it is possible to identify and quantify these trends and take them into account. An observed decrease in sales data for one or two quarters may simply be a typical downward trend in restaurant sales that occurs every year."
Despite the fact that restaurant sales would be expected to change more rapidly in response to a smoking ban than heart attacks, the Helena and Piedmont studies collected data for only 5-6 months after the implementation of smoking bans in those jurisdictions.
Thus, by ANR's own criteria, the Helena and Piedmont studies are not legitimate. Nevertheless, this hasn't stopped ANR from using those studies as the basis for its claim that smoking bans reduce heart attacks by 30-40%.
The Rest of the Story
Since the Piedmont study only examined heart attacks for 5 months following the implementation of Italy's smoking ban and the Helena study only examined heart attacks for 6 months after implementation of the smoking ban in Helena, neither of these studies comes close to meeting ANR's criterion of needing one year of data following a smoking ban before a legitimate conclusion can be drawn regarding the smoking ban's impact.
Therefore, I guess these studies are illegitimate.
What ANR pointed out about fluctuations in restaurant sales can also be said about heart attacks: "The rate of heart attacks changes for many reasons: medical treatments, seasonal variation, and fluctuations due to other superfluous events. Short-term observations cannot accurately evaluate heart attack trends. By collecting data for several years, it is possible to identify and quantify these trends and take them into account. An observed decrease in heart attacks for one or two quarters may simply be a typical downward trend in heart attack incidence."
Based on ANR's own argumentation, there is very real reason to suspect that the Helena et al. conclusions are invalid. At very least, there is strong reason for caution in interpreting the results of these studies.
However, ANR has gone so far as stating that any suggestion that the conclusions of these studies are premature is hogwash: "The Helena Heart Study demonstrates that even a little exposure to secondhand smoke can be deadly. The study is powerful, and demonstrated the urgent need for smokefree laws to protect the public. So it comes as no surprise that the Helena Heart study has unfairly come under attack by the opposition. The opposition has used unsubstantiated claims to argue the validity of this study. These claims are hogwash."
Yet we are to believe that ANR's attack against a slew of economic impact studies that found negative effects of smoking bans on restaurant sales is not hogwash.
I happen to think that ANR's criticism of these particular studies is valid, but if one is to have any consistency at all, then one must also acknowledge that the "opposition's" (I guess I am the opposition) questioning of the validity of the Helena et al. claims is also legitimate, if not valid.
ANR's statement to the public obviously fails to explain why I have criticized the Helena conclusions, since I support smoking bans and so am not "unfairly" attacking the Helena study because it "is powerful, and demonstrated the urgent need for smokefree laws to protect the public."
By the way, even if one accepted the Helena conclusions as the truth, they still do not demonstrate that "even a little exposure to secondhand smoke can be deadly." The study did not ascertain whether the heart attack admissions occurred among smokers or nonsmokers, so it can draw no conclusions on what the contribution of reduced secondhand smoke exposure was to the observed decline in heart attacks.
I take it that ANR would call me "painfully uneducated" since they link to an American Heart Association "fact sheet" that states that the argument that the observed decline in heart attacks in Helena may be due to random variation is painfully uneducated.
I also take it that ANR, and the American Heart Association for that matter are stating that by making my claims, I am "claiming that [I] alone [am] smart enough to draw a conclusion that none of the statisticians at the British Medical Journal and CDC agree with."
That, my friends, is hogwash. First of all, in claiming that there are alternative explanations for the observed findings in Helena, one is not making any claim about how smart one is. Instead, one is simply making a scientific argument. Second, it is wrong to imply that every statistician at the British Medical Journal and every statistician at CDC has agreed with the Helena conclusion.
The truth is that even the scientists at CDC who argued that 30 minutes of secondhand smoke might precipitate heart attacks questioned the validity of the Helena conclusions, pointing out a number of serious limitations of the study methodology that render any definitive conclusions premature:
"Although the results of the study by Sargent and colleagues are consistent with the literature on the risks of acute myocardial infarction associated with secondhand smoke, the study has some important limitations. Firstly, it contains no data on actual exposures to secondhand smoke among residents or cases, and thus no data on the changes in exposure to secondhand smoke that may have occurred after the policy was implemented. It might be reasonable to assume that levels of important smoke toxins within public places in Helena covered by the ordinance dropped dramatically. This effect has been observed in other locations where similar policies have been implemented, with air quality measurements showing 80-90% declines in public places. Even if such declines also occurred in Helena, some proportion of non-smokers would still have been exposed in their homes, cars, or other enclosed places not covered by the ordinance. Thus, without more data, the proportion of non-smokers in Helena among whom exposures were significantly reduced during the six months that the ordinance was in effect cannot be known.
A second concern is that the geographical isolation of the city, while making this type of study feasible, also resulted in a small number of admissions for acute myocardial infarction. As reported elsewhere, the typical number of acute myocardial infarction events per month before the ordinance was only about six or seven and was highly variable, with the actual number per month ranging from none to about 10-12. Although conservative statistical analyses were applied to these data, due to the small number of events and the lack of data on changes in active smoking, random variation and factors other than secondhand smoke exposure may have contributed to the findings.
Finally, the observed effect (a decline of an average of 16 admissions for acute myocardial infarction for a six month period) was substantially greater than what might be expected. With smokers accounting for 38% of the admissions, we can estimate that about 25 admissions (40*—0.62 = 24.8) were among former and never smokers during the equivalent six month period before the ordinance. Even assuming that the proportion of acute myocardial infarction cases among smokers was fairly constant across time, that all non-smokers were frequently exposed to secondhand smoke in public places, that virtually all this exposure was eliminated by the ordinance, and that all coronary heart disease risk related to this exposure was immediately reversed among non-smokers (that is, that risk dropped from 1.3 to 1.0), the maximum impact on admissions for acute myocardial infarction would be predicted to be about 18-19% (0.30*—24.8 = 7.44; 7.44/40 = 18.6%) during the six months that the ordinance was in effect. Taking all of the above assumptions and issues into consideration, a more conservative estimate of the predicted reduction in acute myocardial infarction events might be 10-15%."
According to ANR, therefore, these CDC scientists are part of the opposition which is attacking the Helena study because they despise smoking bans, and their arguments are unsubstantiated claims and pure hogwash.
I think I am finally beginning to understand ANR's logic here. If a study finds results favorable to the anti-smoking agenda, then it is a valid study and is not subject to any criticism. Any questioning of the results of that study must be based on opposition to smoking bans, and must be funded by or commissioned by the tobacco industry, probably through its front groups. Such criticism is hogwash.
If a study finds results unfavorable to the anti-smoking agenda, then it is junk science, probably funded by or commissioned by the tobacco industry through its front groups, and it needs to be countered, preferably by pointing out to the public that the science on the issue is "crystal clear," and thus not subject to any critique or opposing findings.
It's really too bad that I have been kicked out of the movement. I think I'm really beginning to understand the way that things work. I could have made a great career for myself in the movement, now that I really get it.
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