1/14 How do e-cigarettes (ECs) affect cigarette smoking among youth? My new paper with @FloeFoxon simulates each scenario and finds out which one best matches actual trends... https://t.co/dBB7kcnTls @jgitchell @mikepesko @SwitchFinder @jkelovuori @TobPolicy @Clive_Bates

2/14 First, let's talk about why this question is so difficult to answer: COUNTERFACTUALS. We can't know the alternate-reality answers, like which smokers would have never started in a world without ECs, and which nonsmokers would now be smoking without ECs as an option.
3/14 So, the best we can do is use fancy/sophisticated methodologies to estimate what would have happened to youth smoking rates in the absence of ECs. In our case, simulation modeling
4/14 First, we look at the declining smoking trends *that were already happening* before ECs came (~2010), and project them into the present. This is our BASE-CASE SCENARIO about what smoking trends would be if ECs were never invented. Actual trends were LOWER than this base-case
5/14 Side note about terminology: We use the term “catalyst” instead of “gateway,” because “catalyst” is more precise about the claim we are modeling (that ECs are used first, and then causally lead to smoking). Whereas "gateway" can include other mechanisms like renormalization.
6/14 Starting from the base-case scenario, we "switch on" a catalyst effect, where EC users also start smoking. We assume a worst-case scenario, where ALL dual users have gotten there because of a catalyst effect -- this FURTHER overpredicts actual trends.
7/14 So... gateway doesn't fit reality (at the population level)
8/14 Then, starting again from the base-case scenario, we "switch on" a diversion effect, where EC users are prevented from ever becoming smokers. This is closer to the actual trends, but still overpredicts -- meaning a stronger diversion effect is needed to explain reality!
9/14 So, we optimized the simulation model to find *how large a diversion effect would have to be*, to match real-world trends: exponential decay constant of 55.4% of EC users/year are prevented from ever smoking!
10/14 What’s an exponential decay constant? It’s related to the concept of half-life. # of EC users is assumed to decay exponentially if left alone – a standard modeling assumption. 55.4% describes how fast this decline occurs – higher means more EC users prevented from smoking.
11/14 Finally, we "switched on" both effects -- figuring that ECs may act as a catalyst for some, and a diversion for others. Even in the presence of an opposing catalyst effect, *a net diversion effect is necessary* to explain actual trends (of 65.4% EC users/year).
12/14 All together, real data are MUCH more consistent with a diversion effect (and a rather strong one at that!), than a null effect or catalyst/gateway effect.
13/14 Caveats: This doesn’t conclusively prove a diversion effect, but it does show that population-level trends are much better explained by a *net* diversion effect, and are wildly inconsistent with a net catalyst effect. https://t.co/pTYbsCl1hd
14/14 Disclosures: I now work for PinneyAssociates, which consults for JUUL Labs on tobacco harm reduction. However, this study was completed and submitted BEFORE these activities began, in a purely academic position. In fact, my line of research is why I joined Pinney!

More from Society

It is simply not correct to point fingers at wind & solar energy as we try to understand the situation in TX. The system (almost) had a plan for weather (almost) like this. 1/x


It relied on very little wind energy - that was the plan. It relied on a lot of natural gas - that was the plan. It relied on all of its nuclear energy - that was the plan. 2/x

There was enough natural gas, coal and nuclear capacity installed to survive this event - it was NOT "forced out" by the wind energy expansion. It was there. 3/x

Wind, natural gas, coal and nuclear plants all failed to deliver on their expectations for long periods of time. The biggest gap was in natural gas! The generators were there, but they were not able to deliver. 4/x

It may be fair to ask why there is so much wind energy in ERCOT if we do NOT expect it to deliver during weather events like this, but that is an entirely different question - and one with a lot of great answers!! 5/x

You May Also Like

राम-रावण युद्ध समाप्त हो चुका था। जगत को त्रास देने वाला रावण अपने कुटुम्ब सहित नष्ट हो चुका था।श्रीराम का राज्याभिषेक हुआ और अयोध्या नरेश श्री राम के नेतृत्व में चारों दिशाओं में शन्ति थी।
अंगद को विदा करते समय राम रो पड़े थे ।हनुमान को विदा करने की शक्ति तो राम में थी ही नहीं ।


माता सीता भी हनुमान को पुत्रवत मानती थी। अत: हनुमान अयोध्या में ही रह गए ।राम दिनभर दरबार में, शासन व्यवस्था में व्यस्त रहते थे। संध्या को जब शासकीय कार्यों में छूट मिलती तो गुरु और माताओं का कुशल-मंगल पूछ अपने कक्ष में जाते थे। परंतु हनुमान जी हमेशा उनके पीछे-पीछे ही रहते थे ।


उनकी उपस्थिति में ही सारा परिवार बहुत देर तक जी भर बातें करता ।फिर भरत को ध्यान आया कि भैया-भाभी को भी एकांत मिलना चाहिए ।उर्मिला को देख भी उनके मन में हूक उठती थी कि इस पतिव्रता को भी अपने पति का सानिध्य चाहिए ।

एक दिन भरत ने हनुमान जी से कहा,"हे पवनपुत्र! सीता भाभी को राम भैया के साथ एकांत में रहने का भी अधिकार प्राप्त है ।क्या आपको उनके माथे पर सिन्दूर नहीं दिखता?इसलिए संध्या पश्चात आप राम भैया को कृप्या अकेला छोड़ दिया करें "।
ये सुनकर हनुमान आश्चर्यचकित रह गए और सीता माता के पास गए ।


माता से हनुमान ने पूछा,"माता आप अपने माथे पर सिन्दूर क्यों लगाती हैं।" यह सुनकर सीता माता बोलीं,"स्त्री अपने माथे पर सिन्दूर लगाती है तो उसके पति की आयु में वृद्धि होती है और वह स्वस्थ रहते हैं "। फिर हनुमान जी प्रभु राम के पास गए ।