Category Archives: Comment

Why I took part in the “Preregistration Challenge”

By Sarah Peters

The preregistration of study protocols has a long history in clinical trials, but is a more recent innovation in many other areas. The hope is that it will help counter the “reproducibility crisis” in psychological science – the failure of many published findings to replicate reliably. Here I discuss my experience with the Open Science Framework “Preregistration challenge”, and argue for more widespread adoption of preregistering reports.

There is an ongoing methodological crisis in psychological science – the reproducibility crisis refers to the failure of many scientific findings to be replicated. The Reproducibility Project, a recent initiative led by Professor Brian Nosek at the University of Virginia, aimed to identify the scale of this crisis. A large collaboration between 270 project members reran 100 published psychological experiments, and found that just 36% of the initial findings were replicated. Similarly, some classic textbook experiments have proven difficult to replicate, and publication bias – whereby positive findings are more likely to be published and negative findings to be dismissed – plagues the field.

Given this, scientists are exploring how to improve the way we conduct research and thereby improve the quality of what we produce. One suggestion is to preregister our research question, methods and analysis plan in advance of data collection. It is hoped that public preregistration will limit analytical flexibility and post hoc hypothesising, thereby improving the transparency and robustness of research findings.

Curious about the benefits of preregistration, and to see how it differed from the way I’d previously conducted my research, my colleagues and I published a preregistration for a recent study on Open Science Framework (OSF). We were interested in whether Cognitive Bias Modification, a psychological intervention designed to shift the emotional interpretation of faces, would impact clinically-relevant outcomes. We also entered the study into OSF’s (ongoing!) Preregistration Challenge, which offers the chance to win a $1,000 prize to 1,000 researchers who go from preregistration to publication.

Preregistering our study did require a greater time commitment prior to running it, but thinking about our predictions, design, and analyses meant that we could spot any potential issues and improve our experimental design before we collected data (i.e., before it was too late!). As a preregistration is public and cannot be changed after it’s published, it forced us to think more carefully about our decisions. For example, thinking more carefully about whether our data would truly answer our question made us wonder whether the emotional biases we wanted to study might be more prominent when an individual is under stress, so we decided to include another task to measure this. Also, by knowing which statistical analyses we would conduct before recruiting participants we could ensure that our study was adequately powered and would meet the assumptions of the planned analyses.

Initially I was concerned that this approach could be limiting. What if we found something interesting that we hadn’t expected and wanted to run additional analyses to probe it? But a preregistered report doesn’t prevent that – it simply means that you would (honestly and transparently!) report those analyses as exploratory. This protection against HARKing (hypothesising after the results are known) is important; separating analyses as planned versus exploratory can prevent overconfidence in weaker findings and the publication of attractive, but uncertain, positive findings.

Following data collection, we went back to our preregistration. It was here that our earlier time investment paid off; once our data were cleaned we could immediately run our planned analyses, and much of the manuscript writing (introduction and methods) was already done. We also ran a number of exploratory analyses, such as whether our results were moderated by participants’ anxiety scores. We subsequently published our findings in the academic journal Royal Society Open Science, and were thrilled to receive one of the latest $1,000 Preregistration Challenge prizes for bringing our study from preregistration to publication!

While interpreting findings and making discoveries is an important aim of scientific research, it is just as important to continuously scrutinise the scientific method. As a scientist, there is no question that seeing data can influence my decisions and interpretations. However, the adoption of preregistration can eliminate this, make the process easier in the long term, and improve research quality overall.

Professor Nosek and other members of the Reproducibility Project argue that, “Progress in science is marked by reducing uncertainty about nature”. But, if scientific findings have not or cannot be replicated, we can’t be certain that they exist. Preregistration is a simple change to the way we do research that can help to halt the reproducibility crisis and produce effective and credible science.

Read more about how to take part in the Preregistration Challenge here.

See Peters et al.’s preregistration here, and the published study here.

Sarah Peters can be contacted via email at:

A Summary of the E-cigarettes Summit 2016

by Jasmine Khouja @jasmine_khouja

On the 17th November I attended the E-cigarette Summit 2016 at the Royal Society in London. The summit brought together researchers, policy-makers, smoking cessation services and industry members to hear about the latest research, developments and challenges in the e-cigarette domain.

The summit was a one-day event packed full of information with 20 fast-paced (10-20 minutes) talks and 4 panel discussions. My five take home points from the summit were:

  1. Communication

One point which was raised on multiple occasions was that good communication of the research into e-cigarettes is key to the public understanding the risks and benefits of e-cigarette use. Unfortunately, the consensus was that the communication of e-cigarette research to the public is poor. Astonishingly, one speaker commented that someone had asked their daughter: “Is your dad still selling e-cigarettes and killing people?” This demonstrates how badly e-cigarettes have been portrayed, despite general consensus that they are much less harmful than cigarettes. Researchers are trying to communicate their research but face hurdles; some journals may be less likely to publish articles that are positive about vaping, meaning that it is harder to publish evidence that vaping is not as bad for you as cigarettes. The media are also hampering researchers’ efforts as they prefer stories which are anti-vaping and sometimes draw inaccurate conclusions from the evidence, which makes for more interesting stories. However, effective communication of the research is possible: Professor Peter Hajek and Dr Alex Freeman provided some useful advice to researchers which included not inferring human risks from animal studies, ensuring risks are directly compared to those of smoking, being a trustworthy source by being competent, honest and reliable, and providing neutral information without recommendations allowing the public to make their own informed decisions.

  1. The British Medical Association’s Guidelines

Communication of the benefits and risks of e-cigarettes isn’t limited to publications and the media; doctors are being asked about e-cigarettes by patients. Despite the evidence that the research community has provided that e-cigarettes are less harmful than cigarettes, the British Medical Association are yet to update their guidelines to encourage smokers to switch to e-cigarettes. There seemed to be apprehension stemming from the lack of known long-term effects, despite the fact that we know there are vastly fewer and reduced amounts of toxicants in e-cigarettes compared to cigarettes meaning the likelihood of long-term effects as bad as or worse than smoking are extremely unlikely.

  1. Recent Research

Many new studies were presented but the study that really caught my attention was discussed by Dr Lynne Dawkins. Lynne provided evidence for increased puffing behavior when participants are given lower doses of nicotine in their e-cigarettes [1]. She concluded that inhaling more vapour to receive the same amount of nicotine exposes vapers to unnecessary amounts of toxicants. This is very topical as the regulations set out by the Tobacco Products Directive (TPD) which will be fully implemented by May 2017 limit doses to 20 mg/mL meaning that some higher dosage (36 mg/mL) users may expose themselves to extra toxicants to receive the levels of nicotine they need when the higher dosage product become unavailable in the next six months.

  1. The Tobacco Products Directive

The TPD provides some form of regulation for e-cigarette manufacturers and distributors. The inclusion of e-cigarettes in the TPD was controversial due to e-cigarettes not containing tobacco and the restrictive nature of the regulations which were seen as unnecessary by some users and industry members. Part of the regulations included the thorough testing of e-cigarette products to ensure they were safe and the publication of the contents (including toxicants) so that the public could make informed decisions. To my dismay, I was informed that the information submitted by the e-cigarette companies so far will not be made publically accessible for roughly six months due to a system error. I was also informed that compliance with the regulations was low and that age of sale restrictions in particular did not seem to be being enforced. The system and enforcement of the TPD in relation to e-cigarettes needs improving so that consumers can access the information which the TPD states they should have access to and to protect young people whose brain development may be adversely affected by consuming nicotine.

  1. New Systems

As restrictive as the TPD is, new products are still being developed. A new type of e-cigarette is emerging onto the market called pods. These devices are small and similar in size to older less effective designs of e-cigarettes (cigalikes) but have the power and nicotine delivery of the newer more effective tank systems. The sleek, compact designs combined with the improved nicotine delivery systems which prevent overheating (which is associated with harmful byproducts such as formaldehyde) are likely to be very popular. These systems can also record information on how the devices are used (how long individuals puff for and how many puffs they take etc.) which could provide essential information to researchers on how e-cigarettes are used in real life situations.

The day culminated in a key note speech by the Attorney General for Iowa, Tom Miller. He commended the UK’s focus on e-cigarette research and the general positive stance our public health officials have taken in terms of e-cigarettes. He concluded his speech by asking for help from the UK to bring the US up to the same standards.


  1. PMID: 27650300

Teaming up to improve the Psychology PhD

by David Troy @DavidTroy79 and Jim Lumsden @jl9937

Human beings are social creatures; we evolved to work together. Our education system is built around this fact; and throughout school and university we encourage students to team up to solve problems, discuss concepts and answer questions. At the same time, as science advances into the 21st century, we find ourselves trying to answer increasingly difficult questions. These new problems cannot be effectively addressed by one person working alone, and academia and industry are increasingly embracing ‘Team Science’, with many articles ssbeing authored by large groups of individuals with a range of specialisms. As experts in disparate fields, these scientists combine their strengths to triangulate evidence and build robust theories. However, in our experience, the field of experimental psychology has yet to adapt to this model of working, and we suspect this has its root at the very beginning of a psychologist’s career: the solo nature of the psychology PhD. This final stage of training to be a scientist consists of a 3-4 year long solo project which, by its very nature, does not foster close collaboration between researchers. A PhD is a course in independent working – it might teach determination, motivation and self-confidence, but it does not teach teamwork. We believe this needs to change.

A new model:

We would like to see a new model of PhD, based on the kind of team environment found in the software development world. Under this model, a research group would be subdivided into several small teams of scientists, with perhaps 3 or 4 PhD students and a postdoc working very closely together. The group would be located in the same office and tackle research questions collaboratively. Overall supervision would come from multiple senior academics, but the post-doc would act as team-leader on a day-to-day basis. Other stakeholders such as clinicians, policy makers and industry-partners may be invited to work within the group to improve the translatability and relevance of the research.

The main purpose of a team-PhD would be to work towards publishable projects much like a conventional company works towards product release deassssdlines or software updates. However, this increased emphasis on publications should not come at the cost of rigour and integrity with the primary focus remaining the adequate training of the candidate in scientific best practice during their PhD. By pooling resources and effort, such a team would be able to tackle the questions addressed by a traditional PhD thesis in less time. Joint 1st authorships would be common, with each team member’s contribution made explicit, rather than recognised implicitly via authorship order. A common theme of research chosen by team members (with direction from the post-doc team leader and supervisors) would be apparent from the team’s output over several years, but the studies and directions chosen should not need to be as cohesive as a traditional PhD. Given that a PhD is supposed to be training there is currently far too much focus on producing a coherent output (the “narrative arc”), rather than developing essential skills (not intending to diminish the important skill of clear, concise scientific writing). We are scientists, not novelists, and should be free to move around various fields to where our skills are needed most.

Let’s imagine a typical working day: You’re busy handling the response letter to the reviewers of your team’s latest paper. Every now and again you turn around to ask your teammates “How should we handle this question? Should we run some extra analysis?”. Your colleague beside you is writing the protocol for your group’s next project. She’s writing in Google Docs, so any member of the team can chip in whenever they want to. The experiment is designed collaboratively, and you will collect the data together. When the data are in, two team members handle the analysis, while the others write the introduction and methods. The team leader allocates different roles on each project, so you’re always learning new skills, but never far from help. Each day starts with a 10-minute meeting, discussing the plan for the day and flagging up any new papers that people have read and any good ideas that have arisen in the last 24 hours.

We believe that working together in a small group would bring many benefits: individuals can read papers and report back summarised findings, they can discuss theories, bounce ideas off each other, cross-check analysis and spot mistakes. Together they can run larger samples, read more widely, attempt more complex analyses, discuss more deeply, and so on. This sort of introspection and group effort leads to rigour, improved quality control, and ultimately higher throughput. Working in a team in this way would be motivating, with more camaraderie and positive peer-pressure, compared to the current PhD experience. Expertise would be shared between team members with the end result being a team of researchers competent in essential scientific skills (e.g., programming, statistics, study design, etc.). A team-PhD would also help to combat the isolation so many postgraduate students feel.

In order to accommodate this change to the nature of the PhD, the existing application process, whereby the candidate prepares a research proposal describing their own project, would need to be replaced with a more general application in which the applicant describes their research skills, areas of interest and motivations for long-term study. Successful applicants would be added to the research team most in need of their skillset: if a team is already strong in statistical methods then perhaps a psychologist could add a new perspective, for example.

A change in the PhD structure would also require a change to the assessment process. It is often said that PhD theses ends up in university libraries, never to be read again. Given that PhDs are often publically funded, the time spent altering a publication to fit the narrative arc of a thesis would be better spent dedicated to science that can have tangible impact. University of Bristol, alongside other universities, offers an alternative, if rarely used, PhD by published work. In this format candidates do not submit a thesis, but rather must publish a series of “coherent” works, alongside a commentary on the general direction of their research, its scope and aims. Currently, it takes ~10 years to amass enough publications to qualify for this route; however, it is plausible to alter this to the timeframe of a normal PhD. This format of PhD is more likely to produce high quality scientific output, published in academic journals, rather than rotting on a library shelf. Additionally, a PhD-by-publication still requires an oral examination. This exam would be used to ensure that team-PhD candidates are still capable, independent scientists with a sound understanding of their field, even though the bulk of their research was conducted as part of a team.

The teaming up of researchers with different competencies working on publications may have unintended consequences. It may be difficult to find one person to adequately review such work as is currently the case in neurogenetics for example. A possible remedy would be to restructure the review process to include teams of reviewers, where each member of the team specialises in addressing one of the specialisms described in the paper.ssssssssss

So, how can we move from solo training to team-based training? We suggest it is possible to trial the addition of team science to the PhD process by mandating that new PhD candidates work in a team, as part of their 1st year of study. In recent years, the 1+3 year PhD has become more common, whereby candidates carry out solo mini-projects in their 1st year to acquire experience and training in disparate fields. This could be altered to incorporate close teamwork in the execution of these mini-projects. This would provide an opportunity to examine the everyday benefits and challenges of this new mode of working. This way, students would not be overly disadvantaged when emerging from their PhD into a world of academia still concentrated around the principal investigator model, as the majority of their training would still be focused on generating and implementing their own ideas and developing their own “brand” or intellectual identity as a scientist.


The current model of attaining a PhD in psychology is too focused on solo work. We argue that introducing a more collaborative and cohesive framework to the PhD would aid in the development of research skills and produce more well-rounded PhD graduates equipped to tackle complex research questions. We hope this blog post will spark debate about the suitability of current training for psychological research and generate further ideas on how it can be improved to produce researchers with the skillset necessary for science in the 21st century.


Photo credits:


From number crunching to brains: my experiences of interdisciplinary research

by Michelle Taylor @chelle_bluebird

From TARG to neuroscience

The final six months of a PhD can be a stressful time. Not only are you trying to write up three years of research, wondering whether you have done enough work, but you also need to consider what to do next. I decided to try my hand at something different…


My PhD was in the area of epidemiology, where I was using large datasets (such as the Avon Longitudinal Study of Parents and Children, based here at the University of Bristol) to determine causes and consequences of using various drugs of abuse. My time was mainly spent designing and conducting statistical analyses on data that had already been collected and were available for secondary analysis. I completed this work in TARG and the School of Social and Community Medicine and was lucky enough to be funded by the Wellcome Trust on a PhD programme in molecular, genetic and lifecourse epidemiology. The Wellcome Trust also fund two other PhD programmes at the University of Bristol, one in ‘Neural Dynamics’ and another in ‘Dynamic Cell Biology’. Towards the end of my PhD an opportunity arose – the Elizabeth Blackwell Institute were offering three researchers fellowships to conduct nine months of research with one of the other Wellcome Trust programmes. This would involve changing research area and learning something completely new – and I decided to go for it. I applied to move to the Neural Dynamics programme. As my past research had focused on addiction and mental health, gaining knowledge of the field of neuroscience seemed fitting.


After identifying a potential new supervisor and quickly putting together and submitting an application I was told that I had been successful. I was go
ing to become a neuroscientist for the next nine months. The day after handing in my PhD I headed off to the lab of Matt Jones, a neuroscientist whose research interests include sleep, memory and brain circuitry. I was going to be working on a study that aimed to find out more about how genes influence overnight brain activity and memory in humans. I’ve written a little more about this study at the end of this blog post, just in case you’re interested!

My new lab group were very friendly and welcoming, although at times it seemed like they were talking in a different language. I would attend seminars in my new department and be completely confused within minutes. While I did have some knowledge of neuroscience from reading literature, my knowledge was severely lacking compared to that of my new colleagues. Mind you, I could always get my own back by blinding them with statistics!


The study involved getting participants to stay in our sleep clinic overnight and measuring their brain activity while they slept. I had to learn new methods of data collection, which involved measuring a person’s head to find specific points and gluing on electrodes to measure their brain activity (known as PSG, or polysomnography) [1]. Once these data were collected, the night’s recording needed to be scored into various stages of sleep. We can determine this from the length, height and frequency of the waves on the sleep recording. There are two main stages of sleep: REM (which stands for rapid eye movement) and non-REM. Non-REM can be broken down further into stages 1, 2 and 3 [2,3]. Stage 3 is the deepest stage of sleep, while stage 2 contains oscillations called spindles and K-complexes which are thought to play a role in memory consolidation while we sleep [3]. Learning to score a night’s sleep was something very new to me. I was used to having my data in the form of numbers in a spreadsheet not as wavy lines dominating the computer screen!


At the end of the nine months, I found myself understanding the talks that I went to – I even started to sound like a neuroscientist myself at times. Many things which originally seemed overwhelming (such as collecting PSG data) now feel like second nature, and the wavy lines on a computer screen are now meaningful. While at first the experience seemed daunting, it has no doubt opened my mind and expanded my knowledge. The ability to conduct interdisciplinary research is a well-regarded asset, but this experience has not only enhanced my CV. It has increased my confidence when talking to other researchers, as I have realised that we can all learn something from one another. Most importantly I have learned to look at research from a broader perspective – what does my research mean for other fields? How can it inform other research that is different from my own? It is, of course, combining the answers to all of these questions that will enhance science and in turn have more impact on the wider world.

My neuroscience experience has come to an end and for now, it is back to epidemiology. But I will definitely look back on my time in neuroscience fondly, and, who knows, I might even get the chance to integrate epidemiological research with neuroscience in the future…


A little more about the study

Different parts of our brains communicate with one another as we learn new information during the day. Overnight brain activity then helps us to file memories for long-term storage. Evidence suggests that this process varies naturally in everyone. To help us understand what causes this variation, we are interested in finding out more about how genes influence overnight brain activity in healthy individuals. Studying our genes by specifically testing those who carry particular (naturally occurring) form of them can help us understand their role in shaping the natural variation we see in brain activity. Importantly, understanding this in healthy people can then go on to help us develop new targets for treatments to help the sick. We therefore carried out a study to look at how naturally occurring variation at a particular gene variant affects memory consolidation during sleep.

The gene variant was chosen based on previous studies that have shown that it affects both brain activity and sleep. To do this, we invited back participants from the Avon Longitudinal Study of Parents and Children who had provided us with a DNA sample. Information about their genes had been processed and based on this information they were identified as being carriers or non-carriers of the gene we were interested in. This is a study design known as ‘recall-by-genotype’. We then asked these people to spend two nights in a sleep laboratory, perform some memory based tasks and complete some questionnaires so that we can measure how genetic differences relate to memory and brain activity during sleep.

motionwatch_wrist_smlWhilst participants were in the sleep facility we attached a number of sensors to their head in order to record their brain waves, eye movements and muscle activity. We also used sensors on the chest to measure heart rate and take video and audio recordings to confirm whether or not participants become unsettled during the night. Participants were asked to complete some questionnaires about their sleep behaviour and to carry out a memory task before and after sleep.

For the two weeks in between visits to the sleep laboratory, we asked participants to wear an ‘actiwatch’. An actiwatch looks like a normal watch and records movement, telling us when the participant usually goes to sleep and wakes up. We asked participants to wear the actiwatch on their wrist at all times and asked them to fill in a sleep diary for the two weeks.

What do we hope to find?

actigraphyWe hope to find that individuals who carry our genetic variant of interest differ from those who do not carry the variant on a range of sleep characteristics including the non-REM stage 2 spindles and slow wave oscillations found on stage 3 of non-REM sleep. We also expect to find difference between genotype groups on ability to complete the memory task, and the speed at which they complete the memory task. Finally, we expect to observe a correlation between the stage 2 sleep spindles and the results of the memory task. If we observe these results in our data, then this will suggest that this genotype can influence brain activity during sleep which then in turn can effect a person’s memory, as this memory is not being consolidated as well over night.


Where can I find out more?

A protocol for this study has already been published [4].
Once completed, this study will be published open access within a scientific journal.


[1] Wikipedia – polysomnography

[2] American association of sleep

[3] Wikipedia – sleep (including information on stages, spindles, K-complexes and slow waves)

[4] Hellmich C, Durant C, Jones MW, Timpson NJ, Bartsch U, Corbin LJ (2015) Genetics, sleep and memory: a recall-by-genotype study of ZNF804A variants and sleep neurophysiology. BMC Med Genet 16:96

The European Tobacco Products Directive and the future of e-cigarettes in the UK

By Jasmine Khouja @Jasmine_Khouja

E-cigarettes have become a popular product among smokers and ex-smokers, and Action on Smoking and Health (ASH) estimates that there are 2.6 million current users of e-cigarettes in the UK. As an alternative to tobacco smoking, research commissioned by Public Health England estimates that e-cigarettes are likely to be roughly 95% less harmful. The evidence supporting these popular and effective quitting aids suggests that e-cigarettes could be a powerful tool for harm reduction amongst current smokers but there is still uncertainty over the safety of e-cigarettes. Limited research concerning the effects of long-term use and the current lack of strict regulation of the products has fuelled this uncertainty but new regulations have been introduced into the pre-existing European Tobacco Products Directive (TPD) to rectify this. The updated TPD will come into force on 20th May 2016 with a transitional period allowed by the TPD. UK e-cigarettes and refill containers which are not in compliance with the TPD will be allowed to be released for sale on the UK market until 20th November 2016, but from 20th May 2017 all products sold to consumers will need to be fully compliant with the TPD. The alternative to following the regulations set by the TPD will be for e-cigarettes to gain a medical licence from the Medicines and Healthcare products Regulatory Agency (MHRA) and be regulated as licenced medicinal products to be sold in the UK.

jaz blog

As I am about to commence a PhD investigating the reasons for e-cigarette use, I am interested in what the implications of the directive will be in the UK; will it encourage smokers to switch to e-cigarettes, consequently reducing harm to themselves and others, or will it result in a reduction of available products and cause an increase in relapses to smoking?

I have read the directive and listed some of the key changes that will happen and added my own thoughts on what may happen as a result.

  1. CHANGE: New e-cigarette products must be notified to the MHRA six months before their release to the public. E-cigarette companies will be charged £150 to notify MHRA of a new product and £80 for a modification to an existing product, and will then be charged £60 annually thereafter. POSSIBLE OUTCOMES: The MHRA should have more control over the products on the market and be able to prevent unsafe products entering the market but it may take longer for new products to become available to buy. Additionally, some existing products will be unavailable from 20th May 2017 if they do not to comply with the regulations by 20th November 2016.
  1. CHANGE: Under the TPD, e-liquids will only be allowed where the nicotine concentration does not exceed 20 mg of nicotine per ml of liquid. E-liquids containing more than 20 mg of nicotine per ml of liquid will have to gain a medical licence authorised by the MHRA. POSSIBLE OUTCOMES: People may reduce their doses of nicotine and reduce their addiction if their preferred dosage is no longer available. Fewer high dosage products may be available as gaining a medical licence is an expensive process (estimated between £87,000 and £266,000 annually over ten years for a single device). When current products with high dosages such as 36 mg of nicotine per ml of liquid become unavailable, people may use lower dosages such as 20 mg of nicotine per ml of liquid as a substitute and inhale twice as much vapour to get the same nicotine hit. Nicotine is not the only constituent of vapour though; there are low concentrations of other toxicants, so inhaling more vapour means inhaling more toxicants. Alternatively, current higher dosage users may relapse to tobacco smoking if they feel the lower dosages do not effectively deliver the nicotine hit they need.
  1. CHANGE: Products regulated under the TPD must provide information to the MHRA on the safety and contents of e-cigarette products (including ingredients, toxicants and emissions). Health warnings, instructions for use, information on addictiveness and toxicity must also appear on the packaging and accompanying information leaflet. POSSIBLE OUTCOMES: This should allow e-cigarette users to make informed choices. The notification fees mentioned above will include the storage of this information but the companies may have to bear extra costs in testing their products for the amount of toxicants and emissions produced. These tests will have to comply with the standards set in the TPD and by the MHRA which may prove too costly for smaller e-cigarette companies, forcing them to withdraw products from the market. This could leave the market open to the tobacco industry who generally have greater financial resources available to them. The tobacco industry have to also sustain the tobacco market; a consequence of this may be the deliberate placement of ineffective e-cigarette products on the market to encourage current smokers continue to smoke tobacco and ex-smokers using e-cigarettes relapse.
  1. CHANGE: E-cigarette products will be child-safe, will not break or leak during the refill process, and containers will not exceed 10 ml (refill cartridges will not exceed 2 ml). POSSIBLE OUTCOMES: This should prevent accidents involving children consuming dangerous levels of nicotine. Most changes will be made to newer devices, which require e-liquid refills. If these modifications aren’t made by 20th November 2016 the products will be removed from the market by 20th May 2017.
  1. CHANGE: Under the TPD, cross-border advertising will be banned, which includes in newspapers, radio and TV, but not on billboards and posters. Products will not be allowed to make smoking cessation or health claims. Advertising of products with a medicinal license will be allowed under “over the counter” medicine rules. POSSIBLE OUTCOMES: This should minimise the amount of e-cigarette advertising seen by those who should not use e-cigarettes such as children and non-smokers. However, only e-cigarette companies who can afford a medical licence will be able to advertise on TV and this could mislead people into thinking that these products are more effective than other products.

A possible outcome for many of these changes is the loss of products from the market because of non-compliance with the regulations. Although increased reassurance that e-cigarettes on the market meet certain quality standards may encourage new users, the removal of any e-cigarette product from the market will provide an opportunity for e-cigarette users to relapse to smoking; without their favourite brand or flavour, it may be easier for them to resume smoking again than to find a replacement that suits their needs and taste. This in turn could lead to increased levels of smoking, and therefore harms to both individuals and society as a whole. Additionally, high nicotine dosage e-cigarette users may be encouraged to inhale more vapour and therefore unnecessary amounts of other constituents. However, recent preliminary research findings from ASH UK suggest there are few high dosage users meaning that this should not affect many.

The withdrawal of products is likely to be determined by the cost of making products compliant. Tobacco companies generally have greater financial resources than e-cigarette companies, with the top companies making billions in profit each year, meaning they can afford to make the necessary changes to meet the new regulations. The few e-cigarette companies that are owned by tobacco companies mainly produce ‘cigalikes’ which are the least effective design of e-cigarettes and there is a higher chance of relapsing to smoking when using them compared to later-generation devices. Given that the tobacco-owned e-cigarette companies will probably have greater resources available to them, they could end up with a monopoly on the e-cigarette industry. In fact, this may already be happening; the first medically licensed e-cigarette is a ‘cigalike’ owned by British American Tobacco. This means British American Tobacco could own the only TV-advertised e-cigarette (until another company gains a licence). Consequently, smokers looking to try e-cigarettes may choose less effective devices because they are more widely advertised.

These changes may reassure the general public that the devices will be safe but may lead to many ex-smokers relapsing because they are forced to use e-cigarettes and e-liquids that do not meet their needs, all the while lining the pockets of the tobacco industry by allowing them a monopoly on higher nicotine dosage products. Of course, the possible outcomes stated here are speculative; research will need to be undertaken to evaluate the ongoing impact of the new guidelines.



Photo Credits – Lindsay Fox

Does tobacco cause psychosis?

by Marcus Munafo @MarcusMunafo

This blog originally appeared on the Mental Elf site on 30th July 2015.

Hot on the heels of a recent study suggesting a dose-response relationship between tobacco smoking and subsequent risk of psychosis, a systematic review and meta-analysis (including the data from that prospective study) has now been published, again suggesting that we should be considering the possibility that smoking is a causal risk factor for schizophrenia.

As I outlined in my earlier post, smoking and psychotic illness (e.g., schizophrenia) are highly comorbid, and smoking accounts for much of the reduced life expectancy of people with a diagnosis of schizophrenia. For the most part, it has been assumed that smoking is a form of self-medication, to either alleviate symptoms or help with the side effects of antipsychotic medication.

It's widely thought that people with psychosis or schizophrenia use smoking as a way to self-medicate and relieve their symptoms.


This new study reports the results of a systematic review and meta-analysis of prospective, case-control and cross-sectional studies. The authors hoped to test four hypotheses:

  1. That an excess of tobacco use is already present in people presenting with their first episode of psychosis
  1. That daily tobacco use is associated with an increased risk of subsequent psychotic disorder
  1. That daily tobacco use is associated with an earlier age at onset of psychotic illness
  1. That an earlier age at initiation of smoking is associated with an increased risk of psychotic disorder

The authors followed MOOSE and PRISMA guidelines for the conduct and reporting of systematic reviews and meta-analyses, and searched Embase, Medline and PsycINFO for relevant studies. They included studies that used ICD or DSM criteria for psychotic disorders (including schizophrenia, schizophreniform disorder, schizoaffective disorder, delusional disorder, non-affective psychotic disorder, atypical psychosis, psychotic depression, and bipolar mania with psychotic features).

To test the first hypothesis, studies with a control group were used to calculate an odds ratio. To test the second, prospective studies in which rates of smoking were reported for patients who developed psychotic disorders compared to controls were included, so risk ratios could be calculated. To test the third and fourth, prospective and case-control studies were included, and for the onset of psychosis, cross-sectional studies were also included.

Effect size estimates (weighted mean difference for continuous data, and odds ratios for cross-sectional data or relative risks for prospective data) were combined in a random-effects meta-analysis.


A total of 61 studies comprising 72 independent samples were analysed. The overall sample included 14,555 tobacco users and 273,162 non-users.

  1. The overall prevalence of smoking in people presenting with their first episode of psychosis was higher than controls (12 case-control samples, odds ratio 3.22, 95% CI 1.63 to 6.33, P = 0.001). This supports hypothesis 1.
  2. Compared with non-smokers, the incidence of new psychotic disorders was higher overall (6 longitudinal prospective samples, risk ratio 2.18, 95% CI 1.23 to 3.85, P = 0.007). This supports hypothesis 2.
  3. Daily smokers developed psychotic illness at an earlier age compared with non-smokers (26 samples, weighted mean difference -1.04 years, 95% CI -1.82 to -0.26, P = 0.009). This supports hypothesis 3.
  4. Age at initiation of smoking cigarettes did not differ between patients with psychosis and controls (15 samples, weighted mean difference -0.44 years, 95% CI 1-.21 to 0.34, P = 0.270). This does not support hypothesis 4.

Daily tobacco use is associated with an increased risk of psychosis and an earlier age at onset of psychotic illness.


The authors conclude that the results of their systematic review and meta-analysis show that daily tobacco use is associated with an increased risk of psychotic disorder and an earlier age at onset of psychotic illness, although the magnitude of the association is relatively small.

Interestingly, the authors interpret their results in the context of the Bradford Hill criteria for inferring causality (which consider the strength, consistency, specificity, temporality, biological gradient, plausibility, coherence, experiment, and analogy of an association). They argue that, where these criteria can be applied (the specificity criterion cannot be applied because smoking affects so many disease processes, while the experiment criterion is not met because animal models of psychotic illness that capture important features such as delusions are impossible), they do appear to be met by the evidence available.


There are a number of important limitations to this study, which the authors themselves acknowledge:

  • The first is that all analyses relied on observational data, which makes strong causal inference impossible. Longitudinal prospective studies help somewhat in this respect, but only a small number were available for inclusion in the analysis of risk of developing psychosis between smokers and non-smokers. Moreover, even these studies cannot exclude the possibility that symptoms present before a first full episode of psychosis may have led to smoking initiation (i.e., self medication).
  • Another important limitation is that very few studies measured or adjusted for use of other substances (most importantly, perhaps, cannabis, which has been widely discussed as a potential risk factor for schizophrenia). This is a potentially very important source of bias.

Nevertheless, this is a well-conducted systematic review and meta-analysis that brings together a reasonably large literature. The results appear robust, although given the observational nature of the data, and the fact that only data that were comparable across studies could be meta-analysed, any conclusions regarding causality need to be very tentative.

Very few studies in this review, measured or adjusted for use of other substances such as cannabis.


It seems that we should seriously consider the possibility that smoking is a causal risk factor for schizophrenia. Of course, the data available to date aren’t definitive, and we need to be very cautious about inferring causality from observational data, but this does feel like an area where there is growing, converging evidence from multiple studies using multiple methods.

It’s also worth bearing in mind that even if smoking is a causal risk factor, this does not preclude the possibility that smoking is also used as a form of self-medication. There are several thousand constituents of tobacco smoke; it is possible that some of these alleviate symptoms, while others exacerbate them. For this reason, we shouldn’t assume that nicotine is necessarily the culprit if smoking is indeed a causal risk factor; it may be (and Gurillo and colleagues discuss the biological plausibility of nicotine in this context), but that will need to be tested.

This last point is particularly important in the content of ongoing debate regarding the potential harms and benefits of electronic cigarettes. If smoking does turn out to be a causal risk factor for schizophrenia, then whether nicotine or something else in tobacco smoke is identified as the culprit will have an important bearing on this debate, and attitudes towards these products.

There are several thousands constituents of tobacco smoke; it is possible that some of these alleviate symptoms, while others exacerbate them


Primary paper

Gurillo P, Jauhar S, Murray RM, MacCabe J. (2015) Does tobacco use cause psychosis? Systematic review and meta-analysis. Lancet Psychiatry 2015. doi: 10.1016/S2215-0366(15)00152-2 (Open access paper: features audio interview with authors)

Munafo M. Smoking and risk of schizophrenia: new study finds a dose-response relationship. The Mental Elf, 1 Jul 2015.

– See more at:

The effect of smoking-free psychiatric hospitals on smoking behaviour: more evidence needed

By Olivia Maynard @OliviaMaynard17 

This blog originally appeared on the Mental Elf site on 18th May 2015.

One in three people with mental health illnesses in the UK smoke, as compared with one in five of the general population. In addition, smokers with mental illnesses smoke more heavily, are more dependent on nicotine and are less likely to be given help to quit smoking. As a result, they are more likely to suffer from smoking-related diseases, and on average die 12-15 years earlier than the general population.

Since July 2008, mental health facilities in England have had indoor smoking bans. However, NICE guidelines recommend that all NHS sites, including psychiatric hospitals become completely smoke-free, a recommendation previously examined by the Mental Elf.

This NICE recommendation has been criticised by those who argue that:

  1. Tobacco provides necessary self-medication for the mentally ill;
  2. Smoking cessation interferes with recovery from mental illness;
  3. Smoking cessation is the lowest priority for those with mental illnesses;
  4. People with mental illnesses are not interested in quitting;
  5. People with mental illness cannot quit smoking.

Many people argue that forcing people to quit smoking when they are having an acute mental health episode is tantamount to abuse.

Judith Prochaska, a researcher at Stanford University, has previously addressed each of these arguments (she calls them ‘myths’) (Prochaska, 2011). The abridged summary of the evidence surrounding myths 1, 2 and 3 is that:

  1. Smoking actually worsens mental health outcomes; in fact, the argument that nicotine provides self-medication is one which has been promoted by the tobacco industry itself;
  2. Smoking cessation does not exacerbate mental health outcomes;
  3. Smoking cessation should be a high priority, given that mental health patients are much more likely to die from tobacco-related disease than mental illness.

These are interesting and important arguments and more evidence surrounding them is also available here (Prochaska, 2010).

However, in this blog post I focus on ‘myths’ 4 and 5, drawing on a recent systematic review investigating the impact of a smoke-free psychiatric hospitalisation on patients’ motivations to quit (myth 4) and smoking behavior (myth 5) (Stockings et al., 2014).

This systematic review brings together mostly cross-sectional studies that look at the impact that smoke-free hospitals have on psychiatric inpatients who smoke.

Methods and results

Stockings and colleagues searched for studies examining changes in patients’ smoking-related behaviours, motivation and beliefs either during or following an admission to an adult inpatient psychiatric facility.

Study characteristics

Fourteen studies matched these inclusion criteria, two of which were conducted in the UK. The majority of the studies used a cross-sectional design and none were randomised controlled trials. The studies were all quite different, with the number of participants ranging from 15-467 and the length of admission ranging from 1-990 days. Crucially, the type of smoking ban varied considerably between the studies, so I’ll consider these separately.

Facilities with complete smoking bans

Six studies were conducted in facilities with complete bans. All of these offered nicotine dependence treatment, including nicotine replacement therapy (NRT) or brief advice.

  • Only one of these statistically assessed smoking behaviour, finding that cigarette consumption was lower during admission compared with prior to admission.
  • Three studies assessed smoking behaviour after discharge, finding that the majority of patients resumed smoking within five days. However, there was some evidence from the two larger studies that smoking prevalence was still lower at two weeks and three months post-discharge compared with prior to admission.
  • The one study to statistically assess smoking-related beliefs and motivations found that patients expected to be more successful at quitting following discharge compared with at admission. Higher doses of NRT were related to higher expectations of success.

Facilities with incomplete bans

Eight studies were conducted in facilities with incomplete bans. 

  • Four banned smoking indoors and all of these offered nicotine dependence treatment:
    • Only one of these statistically assessed smoking behaviour, finding that quit attempts increased from 2.2% when smoking was permitted in specific rooms, to 18.4% after the ban.
    • One study that assessed smoking prevalence post-discharge found that all participants (n = 15) resumed smoking.
    • One study found that participants expected to be more successful in smoking cessation post-discharge as compared with at admission.
  • Three allowed smoking in designated rooms, with no nicotine dependence treatment:
    • There were mixed results among the two studies which assessed smoking prevalence during admission.
    • Compared with at admission, there was some evidence of increased motivation to quit smoking.
  • One restricted smoking to five pre-determined intervals per day, with no nicotine dependence treatment:
    • Motivation to quit was lower at discharge compared with at admission.

This review suggests that complete bans are the most effective at encouraging smoking cessation and that NRT or brief advice are crucial.


The authors concluded that:

Smoke-free psychiatric hospitalisation may have the potential to impact positively on patients’ smoking behaviours and on smoking-related motivation and beliefs.

Strengths and limitations

The fourteen studies included in this review were all quite different from each other and had a number of limitations including:

  • Small sample sizes;
  • Incomplete reporting of key outcomes;
  • Failure to use controlled, experimental research designs;
  • Differences in the types of smoking bans in place;
  • Inconsistent provision of nicotine dependence treatment.

These key differences and limitations prevented statistical examination of the results as a whole. This means that making firm conclusions is difficult. There is clearly a need for more research in this area.

This area of research is far from complete, so we cannot make any firm conclusions about smoke-free psychiatric hospitals at this stage.


There is evidence that people with mental illnesses are interested in quitting smoking (myth 4) and that they are able to (myth 5). However, we still need more studies to examine these questions with well-powered (i.e. large sample sizes), high-quality (i.e., experimental) research designs.

The evidence presented in this systematic review suggests that complete bans are the most effective at encouraging smoking cessation and that the provision of nicotine dependence treatment, such as NRT or brief advice, is also crucial.

Although a handful of the studies assessed smoking behaviour after discharge, none of the facilities viewed this as an important outcome. Given the high level of smoking-related disease among those with mental health illnesses, ensuring that individuals remain abstinent from smoking after discharge is important for the continuing good health of these individuals.

Importantly, none of the studies in this review explored the impact of smoke-free legislation on mental health outcomes. Although the evidence suggests that smoking cessation actually improves mental health outcomes, future research should continue to examine this relationship.

Over to you

Do you have a mental health illness yourself, or support someone who does? Do you work with people with mental health illnesses? Should psychiatric hospitals become smoke-free?

We'd love to hear your views about this systematic review and more generally on this often emotive topic. Please use the comment box below to share your knowledge and experience.


Primary paper

Stockings EA. et al (2014) The impact of a smoke-free psychiatric hospitalization on patient smoking outcomes: a systematic review. Aust NZ J Psychiatry 2014 May 12;48(7):617-633. [PubMed abstract]

Other references

Prochaska, J. J. (2010). Failure to treat tobacco use in mental health and addiction treatment settings: A form of harm reduction? Drug and Alcohol Dependence, 110(3), 177-182. doi:

Prochaska, J. J. (2011). Smoking and Mental Illness — Breaking the Link. New England Journal of Medicine, 365(3), 196-198. doi: doi:10.1056/NEJMp1105248


Researching abroad: Cannabis and decision making in the Big Apple

by Michelle Taylor @chelle_bluebird

Setting off for TARGs 2013 annual retreat to Cumberland Lodge in Great Windsor Park, I was looking forward to hearing a talk from an invited guest speaker. Gill had flown in from Columbia University to talk to the group about a recent drug administration study her lab group had completed. The research being conducted by their lab was very different to the epidemiological research that I am used to. Now don’t get me wrong, I thoroughly enjoy the research that I do, but these studies sounded new and exciting. After listening to the talk, the evening activities began with dinner and a quiz. Luckily, I ended up on the same quiz team as Gill, giving me the opportunity to ask more about her research. I decided to grab the bull by the horns and offer my help in one of her future studies, and so my trip to the Big Apple began…

central park 1Nine months later I was on my way to Heathrow for a two month stint collecting data on a cannabis administration study. I was both excited and apprehensive. I have never lived more than a 3 hour drive away from family, and have always been in a city where I have known people. I didn’t know whether I would get homesick, or whether I would make friends on my trip abroad. These feelings of apprehension soon disappeared in the first few hours of my first day at the New York Psychiatric Institute. Everyone I met was so friendly and welcoming, even the many morning commuters who stopped to help the lone Brit who was obviously puzzled by the subway map at 7.30am.

yankeesI was to spend the next six weeks collecting data for a study examining the neuro-behavioural mechanisms of decisions to smoke cannabis at the Substance Use Research Center in the New York Psychiatric Institute at Columbia University. This research centre is unique; it is one of the largest drug administration centre in the world and has licenses to administer a wide variety of drugs, including cannabis, cocaine and heroin. This means that much of the research conducted here is cutting edge. The aim of the study that I would be working on was to shed light on how and why drug abusers repeatedly make decisions to take drugs despite substantial negative consequences. The study used brain imaging (fMRI) to examine the neural and behavioural processes involved in decisions to self-administer cannabis, compared to decisions to eat food, in regular cannabis users. We also examined the influence of drug and food cues on the processes underlying these decisions. To do this, participants were recruited as inpatients and stayed with us in the lab for a week. Data collection for this study is still ongoing, but I will be sure to write another blog post with what we found when the results are available.

coney_2I found this research fascinating and it was a pleasure to be involved in the work carried out in this department. The experience was made even more enjoyable by the people I was working with. There were many office conversations about the British and American slang that was being used, many lunchtime trips to Chipotle (an American fast food restaurant that I am definitely missing since my return to the UK), and several Friday evening trips to the local Irish bar. One office memory that will always stick in my mind was meeting a very accomplished researcher in the field of my PhD, a researcher that was definitely someone I should be impressing. Upon entering this individuals office on an extreme
ly hot New York day, the fan was turned to the meeting area and the smell of cannabis filled the room as the flow of air reached me (I had been administered the drug to a participant earlier that afternoon). Probably not the best first impression I have ever made!

milkshakeI did, of course, take every opportunity to explore New York. I was lucky enough to get tickets to watch the New York Yankees beat the Boston Red Sox at the Yankee Stadium, which was also one of the last games played by baseball-legend Derek Jeter. I made several trips to the American Natural History Museum (my favourite type of museum, and this one cannot be done in a day), and while there saw a live spider show, a 3D film about Great White Sharks and a full T-Rex skeleton. The glorious weather allowed for several leisurely strolls around Central Park. And, of course, the American food definitely needs a mention. If anyone reading this takes a trip over the Atlantic, I would definitely recommend visiting Big Daddy’s Diner for what could be the best milkshake on the planet. And don’t be shy about trying a hotdog from one of the carts that can be found on nearly every street corner. The reason there are so many of them is that they’re delicious! I would also recommend a trip to the Russian Tea Rooms for caviar afternoon tea, an evening at the New York Metropolitan Opera (if that’s your cup of tea), and a trip to Coney Island.

t_rexAlthough it was daunting going abroad for that length of time to begin with, I don’t think I would be having those feelings again and I would definitely jump at any opportunity to work in a different environment in the future. I am very grateful that I am a PhD student in a large working group like TARG, as without this I probably would not have come across opportunities such as this one. This experience has taught me the importance of inter-disciplinary research, and the need for several fields contributing evidence to a much larger research question. Since this trip, I have been successful in a fellowship application allowing me 9 months in a different department at the University of Bristol, an application that I probably would not have made if it wasn’t for my experience at the Columbia University. I am an epidemiologist and do not have any plans to change that; however I do plan to conduct more interdisciplinary research in the future. I would like to that Gill (and everyone in her lab group) for welcoming me and making this trip possible. I look forward to hopefully working with you again in the future…

E-cigarettes and teenagers: cause for concern?

By Marcus Munafo @MarcusMunafo 

This blog originally appeared on the Mental Elf site on 20th April 2015


Electronic cigarettes (e-cigarettes) are a range of products that deliver vapour which typically contains nicotine (although zero-nicotine solutions are available). The name is misleading because some products are mechanical rather than electronic, and because they are not cigarettes. While first-generation products were designed to be visually similar to cigarettes, second- and third-generation products are visually distinctive and come in a variety of shapes and sizes. Critically, these products do not contain tobacco, and are therefore intended to deliver nicotine without the harmful constituents of tobacco smoke.

There has been rapid growth in the popularity and use of e-cigarettes in recent years, accompanied by growth in their marketing. At present they are relatively unregulated in many countries, although countries are introducing various restrictions on their availability and marketing. For example, a ban on sales to under-18s will be introduced in England and Wales in 2015.

These products have stimulated considerable (and often highly polarized) debate in the public health community. On the one hand, if they can support smokers in moving away from smoking they have enormous potential to reduce the harms associated with smoking. On the other hand, the quality and efficacy of these products remains largely unknown and is likely to be highly variable, and data on the long-term consequences of their use (e.g., the inhalation of propylene glycol vapour and flavourings) is lacking. There is also a concern that these products may re-normalise smoking, or act as a gateway into smoking.

E-cigarettes and teenagers: a gateway


This study reports the results of a survey conducted by Trading Standards in the North-West of England on 14 to 17 year-old students. The survey focuses on tobacco-related behaviours, and a question on access to e-cigarettes was introduced in 2013. This enabled identification of factors associated with e-cigarette use among people under 18 years old.

The study used data from the 5th Trading Standards North West Alcohol and Tobacco Survey among 14 to 17 year-olds in North-West England, conducted in 2013. The questionnaire was made available to secondary schools across the region through local authority Trading Standards departments, and delivered by teachers during normal school lessons. Compliance was not recorded, and the sample was not intended to be representative but to provide a sample from a range of communities.

The survey consisted of closed, self-completed questions covering sociodemographic variables, alcohol consumption and tobacco use. There were also questions on methods of access to alcohol and tobacco, as well as involvements in violence when drunk. E-cigarette access was assessed by the question “Have you ever tried or purchased e-cigarettes?”.

The study used data from the North West Alcohol and Tobacco Survey, which asked 14 to 17 year-olds lots of questions about their substance use behaviour.


A total of 114 schools participated, and the total dataset included 18,233 participants, of which some were removed for missing data or spoiled questionnaires (e.g., unrealistic answers), so that the final sample for analysis was 16,193. Some of the main findings of the survey included:

  • In total, 19.2% of respondents reported having accessed e-cigarettes, with this being higher in males than females, and increasing with age and socioeconomic deprivation.
  • Level of e-cigarette access was higher among those who had smoked, ranging from 4.9% of never smokers, through 50.7% of ex-smokers, 67.2% of light smokers and 75.8% of heavy smokers.
  • E-cigarette use was associated with alcohol use, with those who drank alcohol more likely to have accessed e-cigarettes than non-drinkers, as well as with smoking by parents/guardians.

Nearly 1 in 5 of the young people surveyed


The authors conclude that their results raise concerns around the access to e-cigarettes by children, particularly among those who have never smoked cigarettes. They argue that their findings suggest that the children who access e-cigarettes are also those most vulnerable to other forms of substance use and risk-taking behavior, and conclude with a call for the “urgent need for controls on e-cigarette sales to children”. The study has some important strengths, most notably its relatively large size, and ability to determine which respondents were living in rich and poor areas.

Understanding the determinants of e-cigarette use, and patterns of use across different sections of society, is important to inform the ongoing debate around their potential benefits and harms. However, it is also not clear what this study tells us that was not already known. The results are consistent with previous, larger surveys, which show that young people (mostly smokers) are trying e-cigarettes. Critically, these previous surveys have shown that while some young non-smokers are experimenting with electronic cigarettes, progression to regular use among this group is rare. Product labels already indicate that electronic cigarettes are not for sale to under-18s, and in 2014 the UK government indicated that legislation will be brought forward to prohibit the sale of electronic cigarettes to under-18s in England and Wales (although at present no such commitment has been made in Scotland).

This study does not add anything significant to our knowledge about e-cigarettes.


There are a number of important limitations to this study:

  • As the authors acknowledge, this was not meant to be a representative survey, and the results can therefore not be generalized to the rest of the north-west of England, let alone the wider UK.
  • As a cross-sectional survey it was not able to follow up individual respondents, for example to determine whether never smokers using e-cigarettes progress to smoking. This problem is common to most e-cigarette surveys to date.
  • The question asked does not tell us whether the participants actually used the e-cigarette they accessed, or what liquid was purchased with the e-cigarette (e.g., the concentration of nicotine). Zero-nicotine solutions are available, and there is evidence that these solutions are widely used by young people.
  • The results are presented confusingly, with numerous percentages (and percentages of percentages) reported. For example, 4.9% of never smokers reported having accessed e-cigarettes, but this is less than 3% of the overall sample (fewer than 500 out of 16,193 respondents). This is potentially an important number to know, but is not reported directly in the article.


This study does not add much to what is already known. Young people experiment with substances like tobacco and alcohol, and as e-cigarettes have become widely available they have begun to experiment with these too. However, to describe electronic cigarette use as “a new drug use option” and part of “at-risk teenagers’ substance using repertoires” is probably unnecessarily alarmist, given that:

  1. There is evidence that regular use of e-cigarettes among never smokers is negligible
  2. There is little evidence of e-cigarette use acting as a gateway to tobacco use
  3. The likelihood that e-cigarette use will be associated with very low levels of harm

It's alarmist to suggest


Primary reference

Huges K, Bellis MA, Hardcastle KA, McHale P, Bennett A, Ireland R, Pike K. Associations between e-cigarette access and smoking and drinking behaviours in teenagers. BMC Public Health 2015; 15: 244. doi: 10.1186/s12889-015-1618-4

Other references

Young Persons Alcohol and Tobacco Survey 2013. Lancashire County Council’s Trading Standards.