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Although vital to shaping appropriate public health responses, the current data describing trends in the use of nicotine products are not ideal, and may provide an incomplete picture of nicotine habits. In today's episode, Tomasz Jerzyński talks nicotine-use data: how do we collect it, how do we analyse it, and how do we use it?


0:00 - Intro with Joanna Junak
0:34 - What is the substitution effect?
2:58 - Can we gather accurate info on nicotine trends?
3:34 - Data from different studies may introduce nicotine trend distortions
5:04 - Ideal results not possible in reality
5:58 - Substitution effect difficult to measure
6:58 - Is reliable analysis still possible?
8:15 - Dual-use data poorly available
9:45 - Closing remarks


Hello and welcome. I'm Joanna Junak and this is GFN News on GFN.TV. In today's program

Tomasz Jerzyński, sociologist and data scientist at the Robert Zions Institute for Social Studies

at University of Warsaw and Knowledge Action Change London will tell us more about the

substitution effect and dual use. Hi Tom, thank you for joining us today. We have heard

on several occasions about the substitution effect. Can you tell us what it is? In the

field of nicotine harm reduction, the substitution effect is the process of replacing combustible

tobacco and harmful forms of smokeless tobacco with safer products. The most important case

is to replace cigarettes with them. To monitor such a process, it's necessary to monitor

the dynamics of smoking and the use of S&P. The key is to compare trend lines. The best

way to obtain this information is through repeated representative panel surveys. This

type of survey is based on asking the same group of people at successive points in time.

Moreover, to achieve our goal, questions about cigarettes use should be asked alongside questions

about the use of safer nicotine delivery systems. For example, snus in Norway and Sweden, e-cigarettes

in UK and HTP in Japan. This may seem obvious, but it's not. Trends taken from independent

samples, usually from different studies, are of course comparable under many assumptions,

but they never give us as strong evidence as a comparison within a single sample. Disciplinary

panel studies can give us information on changes in prevalence over time between nicotine delivery

systems from a single fixed sample of respondents. This allows us to calculate how many have

switched to safer methods of nicotine delivery, how many have kicked the habit, and how many

have added another to their existing habit. If the sample is representative, the results

obtained can be generalized in the population with a given probability. Of course, this

method is not ideal either. It's extremely expensive and burdened due to the sample shrinking

over time. And are the results of such studies available?

I have never heard of a study meeting both conditions. It means being a longitudinal

panel and involving multiple nicotine delivery systems. I'm not aware of such studies.

So is it not possible to obtain relevant information on this subject?

Of course it is. Instead of such an ideal model, researchers turn to survey from different

points in time, but based on independent samples. Sometimes even to surveys conducted by different

research centers. This means that a different group of respondents is analyzed in each survey,

provided of course that the samples refer to the same region. When the surveys are representative,

researchers can infer changes over time. What are the disadvantages of this approach?

What do recipients of the results of such research have to reckon with?

Such information is of slightly lower quality than that obtained from the panel, as we are

not sure that the observed changes are induced by time. It's possible that the differences

between the two samples are self-induced, for example when the sampling method of one

of both of them are distorted due to external circumstances.

Can you give us an example? Yes, imagine the results of two studies conducted

year after year. They show a significant decrease in smoking and a significant increase in vaping.

You could say that this is a confirmation of a substitution effect, a switching between

nicotine delivery systems. In laboratory settings, yes, but in reality, the samples of these

studies may be skewed. The former may have included many more people from rural areas

than the latter. The prevalence of smoking in rural areas is higher than in urban areas,

and the prevalence of vaping is the opposite. Thus, the observed substitution effect is

a false positive. It's due to differences in sampling and not to actual changes.

So getting representative results is impossible? The situation I mentioned before is an extreme

example. If the entire research process is conducted by an experienced, reputable and

professional institution, we can trust the results. We can assume that the researchers

make every effort to be in line with the principles of methodology. Of course, ideals do not exist

in reality. There is always a fraction of error. The better the quality of research,

the better and more reliable the results. Surveys are not laboratory experiments. They

never provide evidence in the mathematical sense, only confirmations. They describe the

world of propensities as defined by Karl Popper.

So why are confirmations of the substitution effect so rare?

Mapping the use of tobacco and nicotine products is patchy. The WHO promotes the Empower Tobacco

Control Program, the first letter of which refers to monitoring. One of the key points

of monitoring is the collect up-to-date information on the use of tobacco and related products.

This is an extremely difficult task for many countries due to the cost involved. As I mentioned

above, professionalism and quality are expensive. The problem has become more difficult in the

post-pandemic reality of the global crisis, especially given that two time points provide

poor evidence of a trend. In fact, we can start talking about a trend when we have at

least three or more time points. The more time points to catch the trend, the greater

the cost multiplier.

Are there other methods of observing the substitution effect?

Another source of information is the market. It gives us a different kind of information

– retail value and volume instead of actual prevalence in the population. However, changes

in market indicators can be useful as estimators of changes in prevalence. The correlation

between market revenue and product prevalence in the UK and New Zealand is over 19%, which

gives us a pretty good basis for inference. This is how we conducted our analysis of changes

in Japan. Based on the annual and quarterly JTI and PMI reports, we are able to show opposite

trends in the volume of retail sales of cigarettes and HTP sticks. We observe over 94 billion

units, it's almost 52% monotonic decline in cigarette sales since the introduction

of HTP in 2014. During this period, sales of HTP sticks have monotonically increased

to over 70 billion units.

Dual-use is also a hot topic in the public debate. Do you have any information on this


Yes, this is an important point to consider when trying to map safer nicotine delivery

systems is to know to what extent dual-use is prevalent, where use of the safer nicotine

delivery systems is accompanied by combustible tobacco. Dual-use information are what is

not a surprise poorly available. Even if a survey has questions relating to smoking and

use of safer nicotine delivery systems, it is not a common practice to publish statistics

where this information is combined. Given that the raw survey dataset is usually not

publicly available, it is not possible to produce such statistics for our analysis.

Furthermore, the practice of dual-use is also a dynamic process. It's common at the beginning

of the switching process and usually expires naturally ending in success or failure. Currently,

we have only a scrapes of information on the matter. Recent publication by Odani and Tabushi

shows there was up to 30% smokers among HTP users in Japan. In the UK, 38% of vapers also

smoke. But as I said before, this is a floating process and not a stable state.

Thank you Tom. That's all for today. Tune in next time here on GFN TV or on GFN TV podcast.

And don't forget to register for the Global Forum on Nicotine Conference taking place

in Warsaw from the 21st to 24th of June. Thanks for watching or listening. See you next time.