Mislukte tweedehands grap wordt herhaald
Een kleine twee jaar geleden verscheen er een onderzoek van super-anti Stanton Glantz waarin werd beweerd dat, na het invoeren van een rookverbod, het aantal hartaanvallen in de stad Helena drastisch daalde. Dit zogenaamde ‘Helena-wonder’ werd volop bekritiseerd, zowel door journalisten als andere wetenschappers.
Na lang zoeken heeft Stanton Glantz weer een stadje gevonden (Pueblo, Colorado) waar (via zijn bekende manipulatietechnieken) ook een dergelijk effect kon worden ‘vastgesteld’.
Maar nu is er Michael Siegel, (mede-)anti-rokenonderzoeker, die prompt op zijn blog lik op stuk geeft en de onzin van de beweringen van Glantz, c.s. meteen aantoont…..
“The Pueblo study adds to the mountain of evidence that secondhand smoke poses a serious threat to human health.”
The Rest of the Story
While the Pueblo study is important because it adds to the evidence that smoke-free laws may result in a decrease in heart attacks, it does not, in my opinion, add to the evidence that secondhand smoke is a cause of heart attacks.
I do not agree that these findings are not surprising “in light of the overwhelming evidence that secondhand smoke poses serious, even life-threatening risks to health,” I don’t think the conclusion of the study is necessarily “reinforced by the scientific evidence about the impact of secondhand smoke on cardiovascular health,” and I don’t agree that the study “adds to the mountain of evidence that secondhand smoke poses a serious threat to human health.”
Why?
Because the study was unable to (or did not attempt to) determine whether the decrease in heart attacks was attributable to a decrease in secondhand smoke exposure among nonsmokers or to a decrease in cigarette consumption among active smokers (or some combination of the two).
The problem, revealed in the article about the study but not in the Campaign for Tobacco-Free Kids’ press release, is that: “The study didn’t distinguish between smokers and nonsmokers, but rather represented a combination of both smokers and those impacted by secondhand smoke.“
In other words, one cannot conclude from the study that the reduction in heart attacks was due to reduced secondhand smoke exposure among bar and restaurant customers, as opposed to reduced smoking among smokers due to the implementation of the law. The effect of smoke-free laws on reducing cigarette consumption and promoting smoking cessation among smokers has been well-documented.
tobaccoanalysis blog
Smoking Bans and Heart Attacks: Pueblo Edition (analyse)
Pueblo study is blowing smoke (opinie, Denver Post)
BMJ publicatie van Helena studie, met reacties (zie vooral laatste reactie)