Chris Sampson’s journal round-up for 4th 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.

A qualitative investigation of the health economic impacts of bariatric surgery for obesity and implications for improved practice in health economics. Health Economics [PubMed] Published 1st June 2018

Few would question the ‘economic’ nature of the challenge of obesity. Bariatric surgery is widely recommended for severe cases but, in many countries, the supply is not sufficient to satisfy the demand. In this context, this study explores the value of qualitative research in informing economic evaluation. The authors assert that previous economic evaluations have adopted a relatively narrow focus and thus might underestimate the expected value of bariatric surgery. But rather than going and finding data on what they think might be additional dimensions of value, the authors ask patients. Emotional capital, ‘societal’ (i.e. non-health) impacts, and externalities are identified as theories for the types of value that might be derived from bariatric surgery. These theories were used to guide the development of questions and prompts that were used in a series of 10 semi-structured focus groups. Thematic analysis identified the importance of emotional costs and benefits as part of the ‘socioemotional personal journey’ associated with bariatric surgery. Out-of-pocket costs were also identified as being important, with self-funding being a challenge for some respondents. The information seems useful in a variety of ways. It helps us understand the value of bariatric surgery and how individuals make decisions in this context. This information could be used to determine the structure of economic evaluations or the data that are collected and used. The authors suggest that an EQ-5D bolt-on should be developed for ’emotional capital’ but, given that this ‘theory’ was predefined by the authors and does not arise from the qualitative research as being an important dimension of value alongside the existing EQ-5D dimensions, that’s a stretch.

Developing accessible, pictorial versions of health-related quality-of-life instruments suitable for economic evaluation: a report of preliminary studies conducted in Canada and the United Kingdom. PharmacoEconomics – Open [PubMed] Published 25th May 2018

I’ve been telling people about this study for ages (apologies, authors, if that isn’t something you wanted to read!). In my experience, the need for more (cognitively / communicatively) accessible outcome measures is widely recognised by health researchers working in contexts where this is relevant, such as stroke. If people can’t read or understand the text-based descriptors that make up (for example) the EQ-5D, then we need some alternative format. You could develop an entirely new measure. Or, as the work described in this paper set out to do, you could modify existing measures. There are three descriptive systems described in this study: i) a pictorial EQ-5D-3L by the Canadian team, ii) a pictorial EQ-5D-3L by the UK team, and iii) a pictorial EQ-5D-5L by the UK team. Each uses images to represent the different levels of the different dimensions. For example, the mobility dimension might show somebody walking around unaided, walking with aids, or in bed. I’m not going to try and describe what they all look like, so I’ll just encourage you to take a look at the Supplementary Material (click here to download it). All are described as ‘pilot’ instruments and shouldn’t be picked up and used at this stage. Different approaches were used in the development of the measures, and there are differences between the measures in terms of the images selected and the ways in which they’re presented. But each process referred to conventions in aphasia research, used input from clinicians, and consulted people with aphasia and/or their carers. The authors set out several remaining questions and avenues for future research. The most interesting possibility to most readers will be the notion that we could have a ‘generic’ pictorial format for the EQ-5D, which isn’t aphasia-specific. This will require continued development of the pictorial descriptive systems, and ultimately their validation.

QALYs in 2018—advantages and concerns. JAMA [PubMed] Published 24th May 2018

It’s difficult not to feel sorry for the authors of this article – and indeed all US-based purveyors of economic evaluation in health care. With respect to social judgments about the value of health technologies, the US’s proverbial head remains well and truly buried in the sand. This article serves as a primer and an enticement for the use of QALYs. The ‘concerns’ cited relate almost exclusively to decision rules applied to QALYs, rather than the underlying principles of QALYs, presumably because the authors didn’t feel they could ignore the points made by QALY opponents (even if those arguments are vacuous). What it boils down to is this: trade-offs are necessary, and QALYs can be used to promote value in those trade-offs, so unless you offer some meaningful alternative then QALYs are here to stay. Thankfully, the Institute for Clinical and Economic Review (ICER) has recently added some clout to the undeniable good sense of QALYs, so the future is looking a little brighter. Suck it up, America!

The impact of hospital costing methods on cost-effectiveness analysis: a case study. PharmacoEconomics [PubMed] Published 22nd May 2018

Plugging different cost estimates into your cost-effectiveness model could alter the headline results of your evaluation. That might seems obvious, but there are a variety of ways in which the selection of unit costs might be somewhat arbitrary or taken for granted. This study considers three alternative sources of information for hospital-based unit costs for hip fractures in England: (a) spell-level tariffs, (b) finished consultant episode (FCE) reference costs, and (c) spell-level reference costs. Source (b) provides, in theory, a more granular version of (a), describing individual episodes within a person’s hospital stay. Reference costs are estimated on the basis of hospital activity, while tariffs are prices estimated on the basis of historic reference costs. The authors use a previously reported cohort state transition model to evaluate different models of care for hip fracture and explore how the use of the different cost figures affects their results. FCE-level reference costs produced the highest total first-year hospital care costs (£14,440), and spell-level tariffs the lowest (£10,749). The more FCEs within a spell, the greater the discrepancy. This difference in costs affected ICERs, such that the net-benefit-optimising decision would change. The study makes an important point – that selection of unit costs matters. But it isn’t clear why the difference exists. It could just be due to a lack of precision in reference costs in this context (rather than a lack of accuracy, per se), or it could be that reference costs misestimate the true cost of care across the board. Without clear guidance on how to select the most appropriate source of unit costs, these different costing methodologies represent another source of uncertainty in modelling, which analysts should consider and explore.

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Alastair Canaway’s journal round-up for 28th May 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.

Information, education, and health behaviours: evidence from the MMR vaccine autism controversy. Health Economics [PubMed] Published 2nd May 2018

In 1998, Andrew Wakefield published (in the Lancet) his infamous and later retracted research purportedly linking the measles-mumps-rubella (MMR) vaccine and autism. Despite the thorough debunking and exposure of academic skulduggery, a noxious cloud of misinformation remained in the public mind, particularly in the US. This study examined several facets of the MMR fake news including: what impact did this have on vaccine uptake in the US (both MMR and other vaccines); how did state level variation in media coverage impact uptake; and what role did education play in subsequent decisions about whether to vaccinate or not. This study harnessed the National Immunization Survey from 1995 to 2006 to answer these questions. This is a yearly dataset of over 200,000 children aged between 19 to 35 months with detailed information on not just immunisation, but also maternal education, income and other sociodemographics. The NewsLibrary database was used to identify stories published in national and state media relating to vaccines and autism. Various regression methods were implemented to examine these data. The paper found that, unsurprisingly, for the year following the Wakefield publication the MMR vaccine take-up declined by between 1.1%-1.5% (notably less than 3% in the UK), likewise this fall in take-up spilled over into other vaccines take-up. The most interesting finding related to education: MMR take-up for children of college-educated mothers declined significantly compared to those without a degree. This can be explained by the education gradient where more-educated individuals absorb and respond to health information more quickly. However, in the US, this continued for many years beyond 2003 despite proliferation of research refuting the autism-MMR link. This contrasts to the UK where educational link closed soon after the findings were refuted, that is, in the UK, the educated responded to the new information refuting the MMR-Autism link. In the US, despite the research being debunked, MMR uptake was lower in the children of those with higher levels of education for many more years. The author speculates that this contrast to the UK may be a result of the media influencing parents’ decisions. Whilst the media buzz in the UK peaked in 2002, it had largely subsided by 2003. In the US however, the media attention was constant, if not increasing till 2006, and so this may have been the reason the link remained within the US. So, we have Andrew Wakefield and arguably fearmongering media to blame for causing a long-term reduction in MMR take-up in the US. Overall, an interesting study leaning on multiple datasets that could be of interest for those working with big data.

Can social care needs and well-being be explained by the EQ-5D? Analysis of the Health Survey for England. Value in Health Published 23rd May 2018

There is increasing discussion about integrating health and social care to provide a more integrated approach to fulfilling health and social care needs. This creates challenges for health economists and decision makers when allocating resources, particularly when comparing benefits from different sectors. NICE itself recognises that the EQ-5D may be inappropriate in some situations. With the likes of ASCOT, ICECAP and WEMWBS frequenting the health economics world this isn’t an unknown issue. To better understand the relationship between health and social care measures, this EuroQol Foundation funded study examined the relationship between social care needs as measured by the Barthel Index, well-being measured using WEMWBS and also the GGH-12, and the EQ-5D as the measure of health. Data was obtained through the Health Survey for England (HSE) and contained 3354 individuals aged over 65 years. Unsurprisingly the authors found that higher health and wellbeing scores were associated with an increased probability of no social care needs. Those who are healthier or at higher levels of wellbeing are less likely to need social care. Of all the instruments, it was the self-care and the pain/discomfort dimensions of the EQ-5D that were most strongly associated with the need for social care. No GHQ-12 dimensions were statistically significant, and for the WEMWBS only the ‘been feeling useful’ and ‘had energy to spare’ were statistically significantly associated with social care need. The authors also investigated various other associations between the measures with many unsurprising findings e.g. EQ-5D anxiety/depression dimension was negatively associated with wellbeing as measured using the GHQ-12. Although the findings are favourable for the EQ-5D in terms of it capturing to some extent social care needs, there is clearly still a gap whereby some outcomes are not necessarily captured. Considering this, the authors suggest that it might be appropriate to strap on an extra dimension to the EQ-5D (known as a ‘bolt on’) to better capture important ‘other’ dimensions, for example, to capture dignity or any other important social care outcomes. Of course, a significant limitation with this paper relates to the measures available in the data. Measures such as ASCOT and ICECAP have been developed and operationalised for economic evaluation with social care in mind, and a comparison against these would have been more informative.

The health benefits of a targeted cash transfer: the UK Winter Fuel Payment. Health Economics [PubMed] [RePEc] Published 9th May 2018

In the UK, each winter is accompanied by an increase in mortality, often known as ‘excess winter mortality’ (EWM). To combat this, the UK introduced the Winter Fuel Payment (WFP), the purpose of the WFP is an unconditional cash transfer to households containing an older person (those most vulnerable to EWM) above the female state pension age with the intent for this to used to help the elderly deal with the cost of keeping their dwelling warm. The purpose of this paper was to examine whether the WFP policy has improved the health of elderly people. The authors use the Health Surveys for England (HSE), the Scottish health Survey (SHeS) and the English Longitudinal Study of Ageing (ELSA) and employ a regression discontinuity design to estimate causal effects of the WFP. To measure impact (benefit) they focus on circulatory and respiratory illness as measured by: self-reports of chest infection, nurse measured hypertension, and two blood biomarkers for infection and inflammation. The authors found that for those living in a household receiving the payment there was a 6% point reduction (p<0.01) in the incidence of high levels of serum fibrinogen (biomarker) which are considered to be a marker of current infection and are associated with chronic pulmonary disease. For the other health outcomes, although positive, the estimated effects were less robust and not statistically significant. The authors investigated the impact of increasing the age of eligibility for the WFP (in line with the increase of women’s pension age). Their findings suggest there may be some health cost associated with the increase in age of eligibility for WFP. To surmise, the paper highlights that there may be some health benefits from the receipt of the WFP. What it doesn’t however consider is opportunity cost. With WFP costing about £2 billion per year, as a health economist, I can’t help but wonder if the money could have been better spent through other avenues.

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Chris Sampson’s journal round-up for 23rd April 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.

What should we know about the person behind a TTO? The European Journal of Health Economics [PubMed] Published 18th April 2018

The time trade-off (TTO) is a staple of health state valuation. Ask someone to value a health state with respect to time and – hey presto! – you have QALYs. This editorial suggests that completing a TTO can be a difficult task for respondents and that, more importantly, individuals’ characteristics may determine the way that they respond and therefore the nature of the results. One of the most commonly demonstrated differences, in this respect, is the fact that valuations of people’s own health states tend to be higher than health states valued hypothetically. But this paper focuses on indirect (hypothetical) valuations. The authors highlight mixed evidence for the influence of age, gender, marital status, having children, education, income, expectations about the future, and of one’s own health state. But why should we try and find out more about respondents when conducting TTOs? The authors offer 3 reasons: i) to inform sampling, ii) to inform the design and standardisation of TTO exercises, and iii) to inform the analysis. I agree – we need to better understand these sources of heterogeneity. Not to over-engineer responses, but to aid our interpretation, even if we want societally-representative valuations that include all of these variations in response behaviour. TTO valuation studies should collect data relating to the individual respondents. Unfortunately, what those data should be aren’t listed in this study, so the research question in the title isn’t really answered. But maybe that’s something the authors have in hand.

Computer modeling of diabetes and its transparency: a report on the eighth Mount Hood Challenge. Value in Health Published 9th April 2018

The Mount Hood Challenge is a get-together for people working on the (economic) modelling of diabetes. The subject of the 2016 meeting was transparency, with two specific goals: i) to evaluate the transparency of two published studies, and ii) to develop a diabetes-specific checklist for transparent reporting of modelling studies. Participants were tasked (in advance of the meeting) with replicating the two published studies and using the replicated models to evaluate some pre-specified scenarios. Both of the studies had some serious shortcomings in the reporting of the necessary data for replication, including the baseline characteristics of the population. Five modelling groups replicated the first model and seven groups replicated the second model. Naturally, the different groups made different assumptions about what should be used in place of missing data. For the first paper, none of the models provided results that matched the original. Not even close. And the differences between the results of the replications – in terms of costs incurred and complications avoided – were huge. The performance was a bit better on the second paper, but hardly worth celebrating. In general, the findings were fear-confirming. Informed by these findings, the Diabetes Modeling Input Checklist was created, designed to complement existing checklists with more general applications. It includes specific data requirements for the reporting of modelling studies, relating to the simulation cohort, treatments, costs, utilities, and model characteristics. If you’re doing some modelling in diabetes, you should have this paper to hand.

Setting dead at zero: applying scale properties to the QALY model. Medical Decision Making [PubMed] Published 9th April 2018

In health state valuation, whether or not a state is considered ‘worse than dead’ is heavily dependent on methodological choices. This paper reviews the literature to answer two questions: i) what are the reasons for anchoring at dead=0, and ii) how does the position of ‘dead’ on the utility-scale impact on decision making? The authors took a standard systematic approach to identify literature from databases, with 7 papers included. Then the authors discuss scale properties and the idea that there are interval scales (such as temperature) and ratio scales (such as distance). The difference between these is the meaningfulness of the reference point (or origin). This means that you can talk about distance doubling, but you can’t talk about temperature doubling, because 0 metres is not arbitrary, whereas 0 degrees Celsius is. The paper summarises some of the arguments put forward for using dead=0. They aren’t compelling. The authors argue that the duration part of the QALY (i.e. time) needs to have ratio properties for the QALY model to function. Time obviously holds this property and it’s clear that duration can be anchored at zero. The authors then demonstrate that, for the QALY model to work, the health-utility scale must also exhibit ratio scale properties. The basis for this is the assumption that zero duration nullifies health states and that ‘dead’ nullifies duration. But the paper doesn’t challenge the conceptual basis for using dead in health state valuation exercises. Rather, it considers the mathematical properties that must hold to allow for dead=0, and asserts them. The authors’ conclusion that dead “needs to have the value of 0 in a QALY model” is correct, but only within the existing restrictions and assumptions underlying current practice. Nevertheless, this is a very useful study for understanding the challenge of anchoring and explicating the assumptions underlying the QALY model.

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