Meeting round-up: Society for Medical Decision Making 17th Biennial European Conference

The Society for Medical Decision Making (SMDM) held their 17th European Conference between 10th and 12th June at the Stadsgehoorzaal in Leiden, the Netherlands. The meeting was chaired by Anne Stiggelbout and Ewout Steyerberg who, along with Uwe Siebert, welcomed us (early) on Monday morning. Some delegates arrived on Sunday for short courses on a range of topics, from modelling in R and causal inference to the psychology of decision making.

Although based in the US, SMDM holds biennial meetings in Europe which are generally attended by delegates from around the world. Around 300 delegates were in attendance at this meeting, travelling from Toronto to Tehran.

The meeting was ‘Patients Included’ and we were introduced to around 10 patients and caregivers on the first morning. They confidently asked questions and gave comments after the presentations and the plenary, sharing their real-world experience to provide context to findings.

There were five ‘oral abstract’ sessions each comprising six presentations in 15 minute slots (10 minutes long with 5 minutes for audience questions). The sessions covered empirical research relating to physician and patient decision-making, and quantitative valuation and evaluation. Popular applied areas were prostate cancer, breast cancer and precision medicine.

Running in parallel to the oral presentations, workshops were dealing with methodological issues relating to health economics, shared decision-making and psychology.

Four poster sessions, conveniently surrounding the refreshment table, attracted delegates in the morning, breaks and lunch. SMDM provides some of the best poster sessions: posters are always of high quality which means poster sessions are always well attended.

One of the highlights of the meeting was the plenary presentation by Sir David Spiegelhalter who spoke about the challenges of communicating benefits and harms (often probabilities) impartially. Sir David gave examples from the UK’s national breast screening programme to show how presenting information can change people’s interpretation of risk. He also drew on examples of ‘nudges’ which may involve providing information in a persuasive rather than informing way in order to manipulate behaviour. Sir David gave us examples of materials which had been redesigned to improve both patients’ and clinicians’ understanding of the information of benefits and harms. The session concluded with a short video about how Ugandan primary school children have reading comic strips to help interpret information and find facts about the benefits and harms of healthcare interventions.

The European SMDM meeting was thoroughly enjoyable and very interesting. The standard of oral and poster presentations was very high, and the environment was very friendly and conducive to networking.

The next North American meeting is in Montreal (October 2018) and the next European meeting will be in 2020 (location to be confirmed).

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Chris Sampson’s journal round-up for 11th June 2018

Every Monday our authors provide a round-up of some of the most recently published peer reviewed articles from the field. We don’t cover everything, or even what’s most important – just a few papers that have interested the author. Visit our Resources page for links to more journals or follow the HealthEconBot. If you’d like to write one of our weekly journal round-ups, get in touch.

End-of-life healthcare expenditure: testing economic explanations using a discrete choice experiment. Journal of Health Economics Published 7th June 2018

People incur a lot of health care costs at the end of life, despite the fact that – by definition – they aren’t going to get much value from it (so long as we’re using QALYs, anyway). In a 2007 paper, Gary Becker and colleagues put forward a theory for the high value of life and high expenditure on health care at the end of life. This article sets out to test a set of hypotheses derived from this theory, namely: i) higher willingness-to-pay (WTP) for health care with proximity to death, ii) higher WTP with greater chance of survival, iii) societal WTP exceeds individual WTP due to altruism, and iv) societal WTP may exceed individual WTP due to an aversion to restricting access to new end-of-life care. A further set of hypotheses relating to the ‘pain of risk-bearing’ is also tested. The authors conducted an online discrete choice experiment (DCE) with 1,529 Swiss residents, which asked respondents to suppose that they had terminal cancer and was designed to elicit WTP for a life-prolonging novel cancer drug. Attributes in the DCE included survival, quality of life, and ‘hope’ (chance of being cured). Individual WTP – using out-of-pocket costs – and societal WTP – based on social health insurance – were both estimated. The overall finding is that the hypotheses are on the whole true, at least in part. But the fact is that different people have different preferences – the authors note that “preferences with regard to end-of-life treatment are very heterogeneous”. The findings provide evidence to explain the prevailing high level of expenditure in end of life (cancer) care. But the questions remain of what we can or should do about it, if anything.

Valuation of preference-based measures: can existing preference data be used to generate better estimates? Health and Quality of Life Outcomes [PubMed] Published 5th June 2018

The EuroQol website lists EQ-5D-3L valuation studies for 27 countries. As the EQ-5D-5L comes into use, we’re going to see a lot of new valuation studies in the pipeline. But what if we could use data from one country’s valuation to inform another’s? The idea is that a valuation study in one country may be able to ‘borrow strength’ from another country’s valuation data. The author of this article has developed a Bayesian non-parametric model to achieve this and has previously applied it to UK and US EQ-5D valuations. But what about situations in which few data are available in the country of interest, and where the country’s cultural characteristics are substantially different. This study reports on an analysis to generate an SF-6D value set for Hong Kong, firstly using the Hong Kong values only, and secondly using the UK value set as a prior. As expected, the model which uses the UK data provided better predictions. And some of the differences in the valuation of health states are quite substantial (i.e. more than 0.1). Clearly, this could be a useful methodology, especially for small countries. But more research is needed into the implications of adopting the approach more widely.

Can a smoking ban save your heart? Health Economics [PubMed] Published 4th June 2018

Here we have another Swiss study, relating to the country’s public-place smoking bans. Exposure to tobacco smoke can have an acute and rapid impact on health to the extent that we would expect an immediate reduction in the risk of acute myocardial infarction (AMI) if a smoking ban reduces the number of people exposed. Studies have already looked at this effect, and found it to be large, but mostly with simple pre-/post- designs that don’t consider important confounding factors or prevailing trends. This study tests the hypothesis in a quasi-experimental setting, taking advantage of the fact that the 26 Swiss cantons implemented smoking bans at different times between 2007 and 2010. The authors analyse individual-level data from Swiss hospitals, estimating the impact of the smoking ban on AMI incidence, with area and time fixed effects, area-specific time trends, and unemployment. The findings show a large and robust effect of the smoking ban(s) for men, with a reduction in AMI incidence of about 11%. For women, the effect is weaker, with an average reduction of around 2%. The evidence also shows that men in low-education regions experienced the greatest benefit. What makes this an especially nice paper is that the authors bring in other data sources to help explain their findings. Panel survey data are used to demonstrate that non-smokers are likely to be the group benefitting most from smoking bans and that people working in public places and people with less education are most exposed to environmental tobacco smoke. These findings might not be generalisable to other settings. Other countries implemented more gradual policy changes and Switzerland had a particularly high baseline smoking rate. But the findings suggest that smoking bans are associated with population health benefits (and the associated cost savings) and could also help tackle health inequalities.

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Chris Sampson’s journal round-up for 5th February 2018

Every Monday our authors provide a round-up of some of the most recently published peer reviewed articles from the field. We don’t cover everything, or even what’s most important – just a few papers that have interested the author. Visit our Resources page for links to more journals or follow the HealthEconBot. If you’d like to write one of our weekly journal round-ups, get in touch.

Cost-effectiveness analysis of germ-line BRCA testing in women with breast cancer and cascade testing in family members of mutation carriers. Genetics in Medicine [PubMed] Published 4th January 2018

The idea of testing women for BRCA mutations – faulty genes that can increase the probability and severity of breast and ovarian cancers – periodically makes it into the headlines. That’s not just because of Angelina Jolie. It’s also because it’s a challenging and active area of research with many uncertainties. This new cost-effectiveness analysis evaluates a programme that incorporates cascade testing; testing relatives of mutation carriers. The idea is that this could increase the effectiveness of the programme with a reduced cost-per-identification, as relatives of mutation carriers are more likely to also carry a mutation. The researchers use a cohort-based Markov-style decision analytic model. A programme with three test cohorts – i) women with unilateral breast cancer and a risk prediction score >10%, ii) first-degree relatives, and iii) second-degree relatives – was compared against no testing. A positive result in the original high-risk individual leads to testing in the first- and second-degree relatives, with the number of subsequent tests occurring in the model determined by assumptions about family size. Women who test positive can receive risk-reducing mastectomy and/or bilateral salpingo-oophorectomy (removal of the ovaries). The results are favourable to the BRCA testing programme, at $19,000 (Australian) per QALY for testing affected women only and $15,000 when the cascade testing of family members was included, with high probabilities of cost-effectiveness at $50,000 per QALY. I’m a little confused by the model. The model includes the states ‘BRCA positive’ and ‘Breast cancer’, which clearly are not mutually exclusive. And It isn’t clear how women entering the model with breast cancer go on to enjoy QALY benefits compared to the no-test group. I’m definitely not comfortable with the assumption that there is no disutility associated with risk-reducing surgery. I also can’t see where the cost of identifying the high-risk women in the first place was accounted for. But this is a model, after all. The findings appear to be robust to a variety of sensitivity analyses. Part of the value of testing lies in the information it provides about people beyond the individual patient. Clearly, if we want to evaluate the true value of testing then this needs to be taken into account.

Economic evaluation of direct-acting antivirals for hepatitis C in Norway. PharmacoEconomics Published 2nd February 2018

Direct-acting antivirals (DAAs) are those new drugs that gave NICE a headache a few years back because they were – despite being very effective and high-value – unaffordable. DAAs are essentially curative, which means that they can reduce resource use over a long time horizon. This makes cost-effectiveness analysis in this context challenging. In this new study, the authors conduct an economic evaluation of DAAs compared with the previous class of treatment, in the Norwegian context. Importantly, the researchers sought to take into account the rebates that have been agreed in Norway, which mean that the prices are effectively reduced by up to 50%. There are now lots of different DAAs available. Furthermore, hepatitis C infection corresponds to several different genotypes. This means that there is a need to identify which treatments are most (cost-)effective for which groups of patients; this isn’t simply a matter of A vs B. The authors use a previously developed model that incorporates projections of the disease up to 2030, though the authors extrapolate to a 100-year time horizon. The paper presents cost-effectiveness acceptability frontiers for each of genotypes 1, 2, and 3, clearly demonstrating which medicines are the most likely to be cost-effective at given willingness-to-pay thresholds. For all three genotypes, at least one of the DAA options is most likely to be cost-effective above a threshold of €70,000 per QALY (which is apparently recommended in Norway). The model predicts that if everyone received the most cost-effective strategy then Norway would expect to see around 180 hepatitis C patients in 2030 instead of the 300-400 seen in the last six years. The study also presents the price rebates that would be necessary to make currently sub-optimal medicines cost-effective. The model isn’t that generalisable. It’s very much Norway-specific as it reflects the country’s treatment guidelines. It also only looks at people who inject drugs – a sub-population whose importance can vary a lot from one country to the next. I expect this will be a valuable piece of work for Norway, but it strikes me as odd that “affordability” or “budget impact” aren’t even mentioned in the paper.

Cost-effectiveness of prostate cancer screening: a systematic review of decision-analytical models. BMC Cancer [PubMed] Published 18th January 2018

You may have seen prostate cancer in the headlines last week. Despite the number of people in the UK dying each year from prostate cancer now being greater than the number of people dying from breast cancer, prostate cancer screening remains controversial. This is because over-detection and over-treatment are common and harmful. Plenty of cost-effectiveness studies have been conducted in the context of detecting and treating prostate cancer. But there are various ways of modelling the problem and various specifications of screening programme that can be evaluated. So here we have a systematic review of cost-effectiveness models evaluating prostate-specific antigen (PSA) blood tests as a basis for screening. From a haul of 1010 studies, 10 made it into the review. The studies modelled lots of different scenarios, with alternative screening strategies, PSA thresholds, and treatment pathways. The results are not consistent. Many of the scenarios evaluated in the studies were more costly and less effective than current practice (which tended to be the lack of any formal screening programme). None of the UK-based cost-per-QALY estimates favoured screening. The authors summarise the methodological choices made in each study and consider the extent to which this relates to the pathways being modelled. They also specify the health state utility values used in the models. This will be a very useful reference point for anyone trying their hand at a prostate cancer screening model. Of the ten studies included in the review, four of them found at least one screening programme to be potentially cost-effective. ‘Adaptive screening’ – whereby individuals’ recall to screening was based on their risk – was considered in two studies using patient-level simulations. The authors suggest that cohort-level modelling could be sufficient where screening is not determined by individual risk level. There are also warnings against inappropriate definition of the comparator, which is likely to be opportunistic screening rather than a complete absence of screening. Generally speaking, a lack of good data seems to be part of the explanation for the inconsistency in the findings. It could be some time before we have a clearer understanding of how to implement a cost-effective screening programme for prostate cancer.

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