Meeting round-up: Health Economists’ Study Group (HESG) Winter 2018

Last week’s biannual intellectual knees-up for UK health economists took place at City, University of London. We’ve written before about HESG, but if you need a reminder of the format you can read Lucy Abel’s blog post on the subject. This was the first HESG I’ve been to in a while that took place in an actual university building.

The conference kicked off for me with my colleague Grace Hampson‘s first ever HESG discussion. It was an excellent discussion of Toby Watt‘s paper on the impact of price promotions for cola, in terms of quantities purchased (they increase) and – by extension – sugar consumption. It was a nice paper with a clear theoretical framework and empirical strategy, which generated a busy discussion. Nutrition is a subject that I haven’t seen represented much at past HESG meetings, but there were several on the schedule this time around with other papers by Jonathan James and Ben Gershlick. I expect it’s something we’ll see becoming more prevalent as policymaking becomes more insistent.

The second and third sessions I attended were on the relationship between health and social care, which is a pressing matter in the UK, particular with regard to achieving integrated care. Ben Zaranko‘s paper considered substitution effects arising from changes in the relative budgets of health and social care. Jonathan Stokes and colleagues attempted to identify whether the Better Care Fund has achieved its goal of reducing secondary care use. That paper got a blazing discussion from Andrew Street that triggered an insightful discussion in the room.

A recurring theme in many sessions was the challenge of communicating with local decision-makers, and the apparent difficulty in working without a reference case to fall back on (such as that of NICE). This is something that I have heard regularly discussed at least since the Winter 2016 meeting in Manchester. At City, this was most clearly discussed in Emma Frew‘s paper describing the researchers’ experiences working with local government. Qualitative research has clearly broken through at HESG, including Emma’s paper and a study by Hareth Al-Janabi on the subject of treatment spillovers on family carers.

I also saw a few papers that related primarily to matters of research conduct and publishing. Charitini Stavropoulou‘s paper explored whether highly-cited researchers are more likely to receive public funding, while the paper I chaired by Anum Shaikh explored the potential for recycling cost-effectiveness models. The latter was a joy for me, with much discussion of model registries!

There were plenty of papers that satisfied my own particular research interests. Right up my research street was Mauro Laudicella‘s paper, which used real-world data to assess the cost savings associated with redirecting cancer diagnoses to GP referral rather than emergency presentation. I wasn’t quite as optimistic about the potential savings, with the standard worries about lead time bias and selection effects. But it was a great paper nonetheless. Also using real-world evidence was Ewan Gray‘s study, which supported the provision of adjuvant chemotherapy for early stage breast cancer but delivered some perplexing findings about patient-GP decision-making. Ewan’s paper explored technical methodological challenges, though the prize for the most intellectually challenging paper undoubtedly goes to Manuel Gomes, who continued his crusade to make health economists better at dealing with missing data – this time for the case of quality of life data. Milad Karimi‘s paper asked whether preferences over health states are informed. This is the kind of work I enjoy thinking about – whether measures like the EQ-5D capture what really matters and how we might do better.

As usual, many delegates worked hard and played hard. I took a beating from the schedule at this HESG, with my discussion taking place during the first session after the conference dinner (where we walked in the footsteps of the Spice Girls) and my chairing responsibilities falling on the last session of the last day. But in both cases, the audience was impressive.

I’ll leave the final thought for the blog post with Peter Smith’s plenary, which considered the role of health economists in a post-truth world. Happily, for me, Peter’s ideas chimed with my own view that we ought to be taking our message to the man on the Clapham omnibus and supporting public debate. Perhaps our focus on (national) policymakers is too strong. If not explicit, this was a theme that could be seen throughout the meeting, whether it be around broader engagement with stakeholders, recognising local decision-making processes, or harnessing the value of storytelling through qualitative research. HESG members are STRETCHing the truth.

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Thesis Thursday: a guide to sources

Despite our best efforts, we’ve ended up without a guest for Thesis Thursday this month. Rather than try and let the January 2018 edition slide by unnoticed, I thought I should take the opportunity to write something a bit different on the subject.

The premise for Thesis Thursday is that there’s lots of exciting research going on around the world by early career researchers as part of doctoral programmes. One of the reasons we think Thesis Thursday is useful (as well as providing insight into the lives of health economics PhD students) is that it exposes readers to research that they might not otherwise get to see until after a long drawn-out publication process or, worse, that might never see the light of day at all.

In this blog post I’ll provide some insight into how we find candidates for Thesis Thursday and how you – between instalments – can get your thesis fix. Or, more likely, how you might be able to use PhD theses more in your research.

The big databases

There are some major repositories around the world for doctoral theses. If you’re looking for a thesis from a British university then your first stop should be EThOS, hosted by the British Library. The search function will be familiar to anyone who has used a bibliographic database. You can also limit your searches by award year and whether or not the thesis is available for immediate download (more on this in a moment).

A good resource for North American theses (and dissertations) is ProQuest, though it’s unfortunately only available to those with a subscription – institutional or otherwise. There is a health economics subject page with a weak collection of 72 theses (none more recent than 2012). But if you dig deeper using search terms you will find a wealth of PhD outputs from universities you’ve never even heard of. The quality is variable, but there are some excellent pieces of work buried in here. We’ll be trying to publicise them using Thesis Thursday.

There are plenty of other databases that bring together theses from multiple sources; these are simply the databases that I use. Honourable mentions also go to Open Access Theses and Dissertations and the NDLTD archive, which seem to have a better international reach than many others.

Institutional repositories

Most universities have their own internal thesis repositories. Most British universities use the standard EPrints system, so their use is familiar. While I’m reluctant to reinforce the Sheffield-York axis of power, the White Rose thesis repository is particularly useful for health economics theses. It’s a doddle to find the latest theses from ScHARR, CHE, and AUHE, though I’m not entirely convinced that they have complete coverage. Further afield in Europe, Erasmus has a good repository of health economics theses. Or, if you’ve been practising your Dutch, you can find a larger repository that includes the likes of Tilburg and Groningen.

Most theses in institutional repositories are embargoed. This means that it isn’t possible to download the thesis unless you make a special request and are granted permission. These theses aren’t likely to be chosen to be featured on the blog because they pose the additional challenge of trying to get sight of the work itself. I wish everybody would make their thesis freely accessible…

A call for candidates

Today’s Thesis Thursday didn’t happen because we weren’t able to find a guest who felt able to contribute. Recent graduates can be hard to track down. Email addresses stop working and subsequent affiliations (if any) are not always clear. If you would like to feature in an upcoming Thesis Thursday or you’d like to recommend someone, get in touch. We shan’t hold it against you if your thesis is not available online, but please be ready with your PDF!

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Chris Sampson’s journal round-up for 8th January 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.

An empirical comparison of the measurement properties of the EQ-5D-5L, DEMQOL-U and DEMQOL-Proxy-U for older people in residential care. Quality of Life Research [PubMed] Published 5th January 2018

There is now a condition-specific preference-based measure of health-related quality of life that can be used for people with cognitive impairment: the DEMQOL-U. Beyond the challenge of appropriately defining quality of life in this context, cognitive impairment presents the additional difficulty that individuals may not be able to self-complete a questionnaire. There’s some good evidence that proxy responses can be valid and reliable for people with cognitive impairment. The purpose of this study is to try out the new(ish) EQ-5D-5L in the context of cognitive impairment in a residential setting. Data were taken from an observational study in 17 residential care facilities in Australia. A variety of outcome measures were collected including the EQ-5D-5L (proxy where necessary), a cognitive bolt-on item for the EQ-5D, the DEMQOL-U and the DEMQOL-Proxy-U (from a family member or friend), the Modified Barthel Index, the cognitive impairment Psychogeriatric Assessment Scale (PAS-Cog), and the neuropsychiatric inventory questionnaire (NPI-Q). The researchers tested the correlation, convergent validity, and known-group validity for the various measures. 143 participants self-completed the EQ-5D-5L and DEMQOL-U, while 387 responses were available for the proxy versions. People with a diagnosis of dementia reported higher utility values on the EQ-5D-5L and DEMQOL-U than people without a diagnosis. Correlations between the measures were weak to moderate. Some people reported full health on the EQ-5D-5L despite identifying some impairment on the DEMQOL-U, and some vice versa. The EQ-5D-5L was more strongly correlated with clinical outcome measures than were the DEMQOL-U or DEMQOL-Proxy-U, though the associations were generally weak. The relationship between cognitive impairment and self-completed EQ-5D-5L and DEMQOL-U utilities was not in the expected direction; people with greater cognitive impairment reported higher utility values. There was quite a lot of disagreement between utility values derived from the different measures, so the EQ-5D-5L and DEMQOL-U should not be seen as substitutes. An EQ-QALY is not a DEM-QALY. This is all quite perplexing when it comes to measuring health-related quality of life in people with cognitive impairment. What does it mean if a condition-specific measure does not correlate with the condition? It could be that for people with cognitive impairment the key determinant of their quality of life is only indirectly related to their impairment, and more dependent on their living conditions.

Resolving the “cost-effective but unaffordable” paradox: estimating the health opportunity costs of nonmarginal budget impacts. Value in Health Published 4th January 2018

Back in 2015 (as discussed on this blog), NICE started appraising drugs that were cost-effective but implied such high costs for the NHS that they seemed unaffordable. This forced a consideration of how budget impact should be handled in technology appraisal. But the matter is far from settled and different countries have adopted different approaches. The challenge is to accurately estimate the opportunity cost of an investment, which will depend on the budget impact. A fixed cost-effectiveness threshold isn’t much use. This study builds on York’s earlier work that estimated cost-effectiveness thresholds based on health opportunity costs in the NHS. The researchers attempt to identify cost-effectiveness thresholds that are in accordance with different non-marginal (i.e. large) budget impacts. The idea is that a larger budget impact should imply a lower (i.e. more difficult to satisfy) cost-effectiveness threshold. NHS expenditure data were combined with mortality rates for different disease categories by geographical area. When primary care trusts’ (PCTs) budget allocations change, they transition gradually. This means that – for a period of time – some trusts receive a larger budget than they are expected to need while others receive a smaller budget. The researchers identify these as over-target and under-target accordingly. The expenditure and outcome elasticities associated with changes in the budget are estimated for the different disease groups (defined by programme budgeting categories; PBCs). Expenditure elasticity refers to the change in PBC expenditure given a change in overall NHS expenditure. Outcome elasticity refers to the change in PBC mortality given a change in PBC expenditure. Two econometric approaches are used; an interaction term approach, whereby a subgroup interaction term is used with the expenditure and outcome variables, and a subsample estimation approach, whereby subgroups are analysed separately. Despite the limitations associated with a reduced sample size, the subsample estimation approach is preferred on theoretical grounds. Using this method, under-target PCTs face a cost-per-QALY of £12,047 and over-target PCTs face a cost-per-QALY of £13,464, reflecting diminishing marginal returns. The estimates are used as the basis for identifying a health production function that can approximate the association between budget changes and health opportunity costs. Going back to the motivating example of hepatitis C drugs, a £772 million budget impact would ‘cost’ 61,997 QALYs, rather than the 59,667 that we would expect without accounting for the budget impact. This means that the threshold should be lower (at £12,452 instead of £12,936) for a budget impact of this size. The authors discuss a variety of approaches for ‘smoothing’ the budget impact of such investments. Whether or not you believe the absolute size of the quoted numbers depends on whether you believe the stack of (necessary) assumptions used to reach them. But regardless of that, the authors present an interesting and novel approach to establishing an empirical basis for estimating health opportunity costs when budget impacts are large.

First do no harm – the impact of financial incentives on dental x-rays. Journal of Health Economics [RePEc] Published 30th December 2017

If dentists move from fee-for-service to a salary, or if patients move from co-payment to full exemption, does it influence the frequency of x-rays? That’s the question that the researchers are trying to answer in this study. It’s important because x-rays always present some level of (carcinogenic) risk to patients and should therefore only be used when the benefits are expected to exceed the harms. Financial incentives shouldn’t come into it. If they do, then some dentists aren’t playing by the rules. And that seems to be the case. The authors start out by establishing a theoretical framework for the interaction between patient and dentist, which incorporates the harmful nature of x-rays, dentist remuneration, the patient’s payment arrangements, and the characteristics of each party. This model is used in conjunction with data from NHS Scotland, with 1.3 million treatment claims from 200,000 patients and 3,000 dentists. In 19% of treatments, an x-ray occurs. Some dentists are salaried and some are not, while some people pay charges for treatment and some are exempt. A series of fixed effects models are used to take advantage of these differences in arrangements by modelling the extent to which switches (between arrangements, for patients or dentists) influence the probability of receiving an x-ray. The authors’ preferred model shows that both the dentist’s remuneration arrangement and the patient’s financial status influences the number of x-rays in the direction predicted by the model. That is, fee-for-service and charge exemption results in more x-rays. The combination of these two factors results in a 9.4 percentage point increase in the probability of an x-ray during treatment, relative to salaried dentists with non-exempt patients. While the results do show that financial incentives influence this treatment decision (when they shouldn’t), the authors aren’t able to link the behaviour to patient harm. So we don’t know what percentage of treatments involving x-rays would correspond to the decision rule of benefits exceeding harms. Nevertheless, this is an important piece of work for informing the definition of dentist reimbursement and patient payment mechanisms.

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