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NOT PEER REVIEWED
Clive Bates’ commentary on our paper repeats claims we previously addressed . Here, we address seven points, the first is contextual and the remaining are raised in his letter.
1. We note the failure of the author to acknowledge Māori perspectives, in particular their support for endgame measures, concerns in relation to harm minimisation  as outlined in his “all in” strategy, and ethical publishing of research about Indigenous peoples. 
2. We reject the assertion that the basis of our modelling is “weak”. While there is uncertainty around the potential effect of denicotinisation, as this policy hasn’t been implemented, there are strong grounds to believe that it will have a profound impact on reducing smoking prevalence. This is based on both theory and logic (i.e., nicotine is the main addictive component of cigarettes and why most people smoke), and the findings of multiple randomized controlled trials (RCTs) showing that smoking very low nicotine cigarettes (VLNCs) increases cessation rates for diverse populations of people who smoke [4-7].
Our model’s estimated effect on smoking prevalence had wide uncertainty, namely a median of 85.9% reduction over 5 years with a 95% uncertainty interval of 67.1% to 96.3% that produced (appropriately) wide uncertainty in the health impacts. The derivation of this input parameter through expert knowledge elicitation (EKE) is described in the Appendix of our paper. Univariate se...
Our model’s estimated effect on smoking prevalence had wide uncertainty, namely a median of 85.9% reduction over 5 years with a 95% uncertainty interval of 67.1% to 96.3% that produced (appropriately) wide uncertainty in the health impacts. The derivation of this input parameter through expert knowledge elicitation (EKE) is described in the Appendix of our paper. Univariate sensitivity analyses comparing the 67.1% and 96.3% estimates (all other input parameters held at their median value) produced HALY gains ranging from 545,000 to 653,000. Our paper presents this uncertainty transparently.
3. The assertion that the effect size estimate of denicotinisation is based on one randomized trial is incorrect. The author has been informed that this assertion is false on several occasions but even so continues to repeat this claim. We used an EKE process, which is described in the Appendix of our paper. The experts considered many ‘inputs’ to their estimation, of which just one was the evidence from the multiple existing RCTs.
4. We disagree with the author’s characterisation of the EKE process as “arbitrary guesswork”. As Bates himself has noted, expert judgement can provide valuable insight in situations of uncertainty and can “provide a risk-perception ‘anchor’ … following assessment of the evidence that exists.”  We believe that ≥ 5 RCTs demonstrating a relationship between VLNCs and increased smoking cessation constitute a reasonable evidence base to draw upon, particularly when supported by theory/logic and other lines of evidence.
Policy-making often occurs in a context of uncertainty. Denicotinisation is one such example, as we will not know its ‘real world’ impact until it has been implemented. To inform that policy making, it is astute to have estimates of the likely health impact – which requires EKE. Over time, as evidence accrues, such modelling should be updated.
5. As stated in our paper, we did not explicitly model an illicit market. Tight border security in an island nation with no land borders within 1,000 km, reduces the potential of a significant illicit tobacco market. Furthermore, the Aotearoa/New Zealand (A/NZ) Government announced new measures against tobacco smuggling in preparation for the introduction of its ‘endgame’ legislation.  The impact of an illicit tobacco market may be greater in other countries. In A/NZ, the illicit market is small (around 5-6% max) and has not increased greatly despite 10 years of above inflation tobacco excise increases and the introduction of plain packs – interventions which the tobacco industry routinely claims will result in an explosion in the illicit market. This suggests enforcement measures work well in the A/NZ context. Furthermore, given the widespread availability and use by people who smoke of nicotine-containing vaping products in A/NZ, seeking to replace VLNCs with illicit cigarettes is likely to be significantly less common than in jurisdictions where vaping products are not available.
6. It is possible – as Bates asserts – that we have overestimated the health gains from denicotinisation and other endgame policies because the smoking prevalence since 2020, appears to be falling more rapidly than we modelled (meaning the ‘room’ for health gains from an endgame policy is less). We discussed this in our paper.
7. Discussing the public health philosophy of denicotinisation was beyond the scope of our paper. Our focus was only on evaluating the potential health and equity impacts of four interventions included the A/NZ Smoke-free Action Plan 2025.
 Edwards R, Ait Ouakrim D, Wilson T, Waa A, Maddox R, Summers J, Gartner C, Lovett R, Blakely T. The case for denicotinising tobacco in Aotearoa NZ remains strong: response to online critique. November 2022 https://www.phcc.org.nz/briefing/case-denicotinising-tobacco-aotearoa-nz...
 Waa A, Robson B, Gifford H, Smylie J, Reading J, Henderson JA, Henderson PN, Maddox R, Lovett R, Eades S, Finlay S. Foundation for a smoke-free world and healthy Indigenous futures: an oxymoron?. Tobacco Control. 2020 Mar 1;29(2):237-40.
 Maddox R, Drummond A, Kennedy M, et al. Ethical publishing in ‘Indigenous’ contextsTobacco Control Published Online First: 13 February 2023. doi: 10.1136/tc-2022-057702
 Donny EC, Denlinger RL, Tidey JW, Koopmeiners JS, Benowitz NL, Vandrey RG, Al’Absi M, Carmella SG, Cinciripini PM, Dermody SS, Drobes DJ. Randomized trial of reduced-nicotine standards for cigarettes. New England Journal of Medicine. 2015 Oct 1;373(14):1340-9.
 Smith TT, Koopmeiners JS, Tessier KM, Davis EM, Conklin CA, Denlinger-Apte RL, Lane T, Murphy SE, Tidey JW, Hatsukami DK, Donny EC. Randomized trial of low-nicotine cigarettes and transdermal nicotine. American journal of preventive medicine. 2019 Oct 1;57(4):515-24.
 Walker N, Howe C, Bullen C, Grigg M, Glover M, McRobbie H, Laugesen M, Parag V, Whittaker R. The combined effect of very low nicotine content cigarettes, used as an adjunct to usual Quitline care (nicotine replacement therapy and behavioural support), on smoking cessation: a randomized controlled trial. Addiction. 2012 Oct;107(10):1857-67.
 Higgins ST, Tidey JW, Sigmon SC, Heil SH, Gaalema DE, Lee D, Hughes JR, Villanti AC, Bunn JY, Davis DR, Bergeria CL. Changes in cigarette consumption with reduced nicotine content cigarettes among smokers with psychiatric conditions or socioeconomic disadvantage: 3 randomized clinical trials. JAMA network open. 2020 Oct 1;3(10):e2019311-.
 Clive Bates, January 2020. Vaping is still at least 95% lower risk than smoking – debunking a feeble and empty critique. https://clivebates.com/vaping-is-sill-at-least-95-lower-risk-than-smokin...
 Edwards R, Johnson E, Hoek j, Waa A, Tautolo E, Ball J, Stanley J. The smokefree 2025 action plan: key findings from the ITC New Zealand (EASE) project. https://www.phcc.org.nz/briefing/smokefree-2025-action-plan-key-findings...
 Hon Meka WHAITIRI, May 2022. Stubbing out Tobacco smuggling. https://www.beehive.govt.nz/release/stubbing-out-tobacco-smuggling
NOT PEER REVIEWED
I have published a summary critique of this modelling exercise on PubPeer.  This summarises concerns raised in post-publication reviews of this paper while it was in pre-print form by experts from New Zealand and Canada, and me. 
By way of a brief summary:
1. All the important modelled findings flow from a single assumption that denicotinisation will reduce smoking prevalence by 85% over five years. Yet the basis for this assumption is weak and disconnected from the reality of the market system being modelled.
2. The central assumption is based partly on a smoking cessation trial that bears no relation to the market and regulatory intervention that is the subject of the simulation. Even so, the trial findings do not support the modelling assumption.
3. The central assumption also draws on expert elicitation. Yet, there is no experience with this measure as it would be novel, and there is no relevant expertise in this sort of intervention. Where experts have been asked to assess the impacts, their views diverge widely, suggesting that their estimates are mainly arbitrary guesswork.
4. The authors have only modelled benefits and have not included anything that might be a detriment or create a trade-off. The modelling takes no account of the black market or workarounds. These are inevitable consequences of such 'endgame' prohibitions, albeit of uncertain size. Though it may be challenging to mo...
4. The authors have only modelled benefits and have not included anything that might be a detriment or create a trade-off. The modelling takes no account of the black market or workarounds. These are inevitable consequences of such 'endgame' prohibitions, albeit of uncertain size. Though it may be challenging to model, the simulation does not account for the negative behavioural or perceptual impacts of trying to force people to quit or switch by using the law to remove their regular cigarettes. It should not be assumed that these are zero or immaterial to policy assessment.
5. The real-world progress in reducing smoking in New Zealand through tobacco harm reduction and the rise of vaping has been rapid and highly positive, outpacing both the business-as-usual baseline assumptions in the modelling and the impact of the intervention. This suggests the modelled benefits are greatly overstated.
6. The denicotinisation policy should not be compared to a flawed and inflated hypothetical business-as-usual baseline but to an alternative policy that embraces a different public health philosophy. The denicotinisation measure uses the power of the law to try to force behaviour change onto smokers by removing their regular cigarettes from the market. This may be effective, but it also carries risks of black market activity and a public or political backlash once the consequences are understood by those affected. The alternative would position the state as an enabler, maximising support, encouragement and incentives to switch to smoke-free alternatives or quit. This is not business as usual but would mean going “all in” on tobacco harm reduction, with the goal of reducing smoking as rapidly as possible but without resorting to using the coercive power of the law. Such a policy may prove effective but also have lower risks and be less susceptible to unintended consequences.
 Clive Bates, The simulation bears no relation to reality, and its findings are not informative, PubPeer, January 2023 https://pubpeer.com/publications/7F2AAD1105705B0B9F492C97160163#1
 Bates, C., Youdan, B., Bonita, R., Laking, G., Sweanor, D., Beaglehole, R. (2022). Review of: “Tobacco endgame intervention impacts on health gains and Māori:non-Māori health inequity: a simulation study of the Aotearoa-New Zealand Tobacco Action Plan.” Qeios. https://doi.org/10.32388/8WXH0J
 Bates, C., Youdan, B., Bonita, R., Sweanor, D., & Beaglehole, R. (2022). Review of: “The case for denicotinising tobacco in Aotearoa NZ remains strong: response to online critique.” Qeios. https://doi.org/10.32388/ZZAUQM