Meeting round-up: iHEA Congress 2019

Missed iHEA 2019? Or were you there but could not make it to all of the amazing sessions? Stay tuned for my conference highlights!

iHEA started on Saturday 13th with pre-congress sessions on fascinating research as well as more prosaic topics, such as early-career networking sessions with senior health economists. All attendees got a super useful plastic bottle – great idea iHEA team!

The conference proper launched on Sunday evening with the brilliant plenary session by Raj Chetty from Harvard University.

Monday morning started bright and early with the thought-provoking session on validation of CE models. It was chaired and discussed by Stefan Lhachimi and featured presentations by Isaac Corro Ramos, Talitha Feenstra and Salah Ghabri. I’m pleased to see that validation is coming to the forefront of current topics! Clearly, we need to do better in validating our models and documenting code, but we’re on the right track and engaged in making this happen.

Next up, the superb session on the societal perspective for cost-effectiveness analysis. It was an all-star cast with Mark Sculpher, Simon Walker, Susan Griffin, Peter Neumann, Lisa Robinson, and Werner Brouwer. I’ve live-tweeted it here.

The case was expertly made that taking a single sector perspective can be misleading when evaluating policies with cross-sectoral effects, hence the impact inventory by Simon and colleagues is a useful tool to guide the choice of sectors to include. At the same time, we should be mindful of the requirements of the decision-maker for whom CEA is intended. This was a compelling session, which will definitely set the scene for much more research to come.

After a tasty lunch (well done catering team!), I headed to the session on evaluations using non-randomised data. The presenters included Maninie Molatseli, Fernando Antonio Postali, James Love-Koh and Taufik Hidayat, on case studies from South Africa, Brazil and Indonesia. Marc Suhrcke chaired. I really enjoyed hearing about the practicalities of applying econometric methods to estimate treatment effects of system wide policies. And James’s presentation was a great application of distributional cost-effectiveness analysis.

I was on the presenter’s chair next, discussing the challenges in implementing policies in the southwest quadrant of the CE plane. This session was chaired by Anna Vassall and discussed by Gesine Meyer-Rath. Jack Dowie started by convincingly arguing that the decision rule should be the same regardless of where in the CE plane the policy falls. David Bath and Sergio Torres-Rueda presented fascinating case studies of south west policies. And I argued that the barrier was essentially a problem of communication (presentation available here). An energetic discussion followed and showed that, even in our field, the matter is far from settled.

The day finished with the memorial session for the wonderful Alan Maynard and Uwe Reinhardt, both of whom did so much for health economics. It was a beautiful session, where people got together to share incredible stories from these health economics heroes. And if you’d like to know more, both Alan and Uwe have published books here and here.

Tuesday started with the session on precision medicine, chaired by Dean Regier, and featuring Rosalie Viney, Chris McCabe and Stuart Peacock. Rather than slides, the screen was filled with a video of a cosy fireplace, inviting the audience to take part in the discussion.

Under debate was whether precision medicine is a completely different type of technology, with added benefits over and above improvement to health, and needing a different CE framework. The panellists were absolutely outstanding in debating the issues! Although I understand the benefits beyond health that these technologies can offer, I side with the view that, like with other technologies, value is about whether the added benefits are worth the losses given the opportunity cost.

My final session of the day was by the great Mike Drummond, comparing how HTA has influenced the uptake of new anticancer drugs in Spain versus England (summary in thread below). Mike and colleagues found that positive recommendations do increase utilisation, but the magnitude of change differs by country and region. The work is ongoing in checking that utilisation has been picked up accurately in the routine data sources.

The conference dinner was at the Markthalle, with plenty of drinks and loads of international food to choose from. I had to have an early night given that I was presenting at 8:30 the next morning. Others, though, enjoyed the party until the early hours!

Indeed, Wednesday started with my session on cost-effectiveness analysis of diagnostic tests. Alison Smith presented on her remarkable work on measurement uncertainty while Hayley Jones gave a masterclass on her new method for meta-analysis of test accuracy across multiple thresholds. I presented on the CEA of test sequences (available here). Simon Walker and James Buchanan added insightful points as discussants. We had a fantastically engaged audience, with great questions and comments. It shows that the CEA of diagnostic tests is becoming a hugely important topic.

Sadly, some other morning sessions were not as well attended. One session, also on CEA, was even cancelled due to lack of audience! For future conferences, I’d suggest scheduling the sessions on the day after the conference dinner a bit later, as well as having fewer sessions to choose from.

Next up on my agenda was the exceptional session on equity, chaired by Paula Lorgelly, and with presentations by Richard Cookson, Susan Griffin and Ijeoma Edoka. I was unable to attend, but I have watched it at home via YouTube (from 1:57:10)! That’s right, some sessions were live streamed and are still available via the iHEA website. Do have a look!

My last session of the conference was on end-of-life care, with Charles Normand chairing, discussed by Helen Mason, Eric Finkelstein, and Mendwas Dzingina, and presentations by Koonal Shah, Bridget Johnson and Nikki McCaffrey. It was a really thought-provoking session, raising questions on the value of interventions at the end-of-life compared to at other stages of the life course.

Lastly, the outstanding plenary session by Lise Rochaix and Joseph Kutzin on how to translate health economics research into policy. Lise and Joseph had pragmatic suggestions and insightful comments on the communication of health economics research to policy makers. Superb! Also available on the live stream here (from 06:09:44).

iHEA 2019 was truly an amazing conference. Expertly organised, well thought-out and with lots of interesting sessions to choose from. iHEA 2021 in Cape Town is firmly in my diary!

Chris Sampson’s journal round-up for 20th May 2019

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.

A new method to determine the optimal willingness to pay in cost-effectiveness analysis. Value in Health Published 17th May 2019

Efforts to identify a robust estimate of the willingness to pay for a QALY have floundered. Mostly, these efforts have relied on asking people about their willingness to pay. In the UK, we have moved away from using such estimates as a basis for setting cost-effectiveness thresholds in the context of resource allocation decisions. Instead, we have attempted to identify the opportunity cost of a QALY, which is perhaps even more difficult, but more easy to justify in the context of a fixed budget. This paper seeks to inject new life into the willingness-to-pay approach by developing a method based on relative risk aversion.

The author outlines the relationship between relative risk aversion and the rate at which willingness-to-pay changes with income. Various candidate utility functions are described with respect to risk preferences, with a Weibull function being adopted for this framework. Estimates of relative risk aversion have been derived from numerous data sources, including labour supply, lottery experiments, and happiness surveys. These estimates from the literature are used to demonstrate the relationship between relative risk aversion and the ‘optimal’ willingness to pay (K), calibrated using the Weibull utility function. For an individual with ‘representative’ parameters plugged into their utility function, K is around twice the income level. K always increases with relative risk aversion.

Various normative questions are raised, including whether a uniform K should be adopted for everybody within the population, and whether individuals should be able to spend on health care on top of public provision. This approach certainly appears to be more straightforward than other approaches to estimating willingness-to-pay in health care, and may be well-suited to decentralised (US-style) resource allocation decision-making. It’s difficult to see how this framework could gain traction in the UK, but it’s good to see alternative approaches being proposed and I hope to see this work developed further.

Striving for a societal perspective: a framework for economic evaluations when costs and effects fall on multiple sectors and decision makers. Applied Health Economics and Health Policy [PubMed] Published 16th May 2019

I’ve always been sceptical of a ‘societal perspective’ in economic evaluation, and I have written in favour of a limited health care perspective. This is mostly for practical reasons. Being sufficiently exhaustive to identify a truly ‘societal’ perspective is so difficult that, in attempting to do so, there is a very high chance that you will produce estimates that are so inaccurate and imprecise that they are more dangerous than useful. But the fact is that there is no single decision-maker when it comes to public expenditure. Governments are made up of various departments, within which there are many levels and divisions. Not everybody will care about the health care perspective, so other objectives ought to be taken into account.

The purpose of this paper is to build on the idea of the ‘impact inventory’, described by the Second Panel on Cost-Effectiveness in Health and Medicine, which sought to address the challenge of multiple objectives. The extended framework described in this paper captures effects and opportunity costs associated with an intervention within various dimensions. These dimensions could (or should) align with decision-makers’ objectives. Trade-offs invariably require aggregation, and this aggregation could take place either within individuals or within dimensions – something not addressed by the Second Panel. The authors describe the implications of each approach to aggregation, providing visual representations of the impact inventory in each case. Aggregating within individuals requires a normative judgement about how each dimension is valued to the individual and then a judgement about how to aggregate for overall population net benefit. Aggregating across individuals within dimensions requires similar normative judgements. Where the chosen aggregation functions are linear and additive, both approaches will give the same results. But as soon as we start to consider equity concerns or more complex aggregation, we’ll see different decisions being indicated.

The authors adopt an example used by the Second Panel to demonstrate the decisions that would be made within a health-only perspective and then decisions that consider other dimensions. There could be a simple extension beyond health, such as including the impact on individuals’ consumption of other goods. Or it could be more complex, incorporating multiple dimensions, sectors, and decision-makers. For the more complex situation, the authors consider the inclusion of the criminal justice sector, introducing the number of crimes averted as an object of value.

It’s useful to think about the limitations of the Second Panel’s framing of the impact inventory and to make explicit the normative judgements involved. What this paper seems to be saying is that cross-sector decision-making is too complex to be adequately addressed by the Second Panel’s impact inventory. The framework described in this paper may be too abstract to be practically useful, and too vague to be foundational. But the complexities and challenges in multi-sector economic evaluation need to be spelt out – there is no simple solution.

Advanced data visualisation in health economics and outcomes research: opportunities and challenges. Applied Health Economics and Health Policy [PubMed] Published 4th May 2019

Computers can make your research findings look cool, which can help make people pay attention. But data visualisation can also be used as part of the research process and provide a means of more intuitively (and accurately) communicating research findings. The data sets used by health economists are getting bigger, which provides more opportunity and need for effective visualisation. The authors of this paper suggest that data visualisation techniques could be more widely adopted in our field, but that there are challenges and potential pitfalls to consider.

Decision modelling is an obvious context in which to use data visualisation, because models tend to involve large numbers of simulations. Dynamic visualisations can provide a means by which to better understand what is going on in these simulations, particularly with respect to uncertainty in estimates associated with alternative model structures or parameters. If paired with interactive models and customised dashboards, visualisation can make complex models accessible to non-expert users. Communicating patient outcomes data is also highlighted as a potential application, aiding the characterisation of differences between groups of individuals and alternative outcome measures.

Yet, there are barriers to wider use of visualisation. There is some scepticism about bias in underlying analyses, and end users don’t want to be bamboozled by snazzy graphics. The fact that journal articles are still the primary mode of communicating research findings is a problem, as you can’t have dynamic visualisations in a PDF. There’s also a learning curve for analysts wishing to develop complex visualisations. Hopefully, opportunities will be identified for two-way learning between the health economics world and data scientists more accustomed to data visualisation.

The authors provide several examples (static in the publication, but with links to live tools), to demonstrate the types of visualisations that can be created. Generally speaking, complex visualisations are proposed as complements to our traditional presentations of results, such as cost-effectiveness acceptability curves, rather than as alternatives. The key thing is to maintain credibility by ensuring that data visualisation is used to describe data in a more accurate and meaningful way, and to avoid exaggeration of research findings. It probably won’t be long until we see a set of good practice guidelines being developed for our field.

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Alastair Canaway’s journal round-up for 30th July 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.

Is there an association between early weight status and utility-based health-related quality of life in young children? Quality of Life Research [PubMed] Published 10th July 2018

Childhood obesity is an issue which has risen to prominence in recent years. Concurrently, there has been an increased interest in measuring utility values in children for use in economic evaluation. In the obesity context, there are relatively few studies that have examined whether childhood weight status is associated with preference-based utility and, following, whether such measures are useful for the economic evaluation of childhood obesity interventions. This study sought to tackle this issue using the proxy version of the Health Utilities Index Mark 3 (HUI-3) and weight status data in 368 children aged five years. Associations between weight status and HUI-3 score were assessed using various regression techniques. No statistically significant differences were found between weight status and preference-based health-related quality of life (HRQL). This adds to several recent studies with similar findings which imply that young children may not experience any decrements in HRQL associated with weight status, or that the measures we have cannot capture these decrements. When considering trial-based economic evaluation of childhood obesity interventions, this highlights that we should not be solely relying on preference-based instruments.

Time is money: investigating the value of leisure time and unpaid work. Value in Health Published 14th July 2018

For those of us who work on trials, we almost always attempt to do some sort of ‘societal’ perspective incorporating benefits beyond health. When it comes to valuing leisure time and unpaid work there is a dearth of literature and numerous methodological challenges which has led to a bit of a scatter-gun approach to measuring and valuing (usually by ignoring) this time. The authors in the paper sought to value unpaid work (e.g. household chores and voluntary work) and leisure time (“non-productive” time to be spent on one’s likings, nb. this includes lunch breaks). They did this using online questionnaires which included contingent valuation exercises (WTP and WTA) in a sample of representative adults in the Netherlands. Regression techniques following best practice were used (two-part models with transformed data). Using WTA they found an additional hour of unpaid work and leisure time was valued at €16 Euros, whilst the WTP value was €9.50. These values fall into similar ranges to those used in other studies. There are many issues with stated preference studies, which the authors thoroughly acknowledge and address. These costs, so often omitted in economic evaluation, have the potential to be substantial and there remains a need to accurately value this time. Capturing and valuing these time costs remains an important issue, specifically, for those researchers working in countries where national guidelines for economic evaluation prefer a societal perspective.

The impact of depression on health-related quality of life and wellbeing: identifying important dimensions and assessing their inclusion in multi-attribute utility instruments. Quality of Life Research [PubMed] Published 13th July 2018

At the start of every trial, we ask “so what measures should we include?” In the UK, the EQ-5D is the default option, though this decision is not often straightforward. Mental health disorders have a huge burden of impact in terms of both costs (economic and healthcare) and health-related quality of life. How we currently measure the impact of such disorders in economic evaluation often receives scrutiny and there has been recent interest in broadening the evaluative space beyond health to include wellbeing, both subjective wellbeing (SWB) and capability wellbeing (CWB). This study sought to identify which dimensions of HRQL, SWB and CWB were most affected by depression (the most common mental health disorder) and to examine the sensitivity of existing multi-attribute utility instruments (MAUIs) to these dimensions. The study used data from the “Multi-Instrument Comparison” study – this includes lots of measures, including depression measures (Depression Anxiety Stress Scale, Kessler Psychological Distress Scale); SWB measures (Personal Wellbeing Index, Satisfaction with Life Scale, Integrated Household Survey); CWB (ICECAP-A); and multi-attribute utility instruments (15D, AQoL-4D, AQoL-8D, EQ-5D-5L, HUI-3, QWB-SA, and SF-6D). To identify dimensions that were important, the authors used the ‘Glass’s Delta effect size’ (the difference between the mean scores of healthy and self-reported groups divided by the standard deviation of the healthy group). To investigate the extent to which current MAUIs capture these dimensions, each MAUI was regressed on each dimension of HRQL, CWB and SWB. There were lots of interesting findings. Unsurprisingly, the most important dimensions were in the psychosocial dimensions of HRQL (e.g. the ‘coping’, ‘happiness’, and ‘self-worth’ dimensions of the AQoL-8D). Interestingly, the ICECAP-A proved to be the best measure for distinguishing between healthy individuals and those with depression. The SWB measures, on the other hand, were less impacted by depression. Of the MAUIs, the AQoL-8D was the most sensitive, whilst our beloved EQ-5D-5L and SF-6D were the least sensitive at distinguishing dimensions. There is a huge amount to unpack within this study, but it does raise interesting questions regarding measurement issues and the impact of broadening the evaluative space for decision makers. Finally, it’s worth noting that a new MAUI (ReQoL) for mental health has been recently developed – although further testing is needed, this is something to consider in future.

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