Chris Sampson’s journal round-up for 13th March 2017

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.

The effects of exercise and relaxation on health and wellbeing. Health Economics [PubMedPublished 9th Month 2017

Encouraging self-management of health sounds like a good idea, but the evidence is pretty weak. As economists, we know that something must be displaced in order to do it. This study considers the opportunity cost of time and how it might affect self-management activity and any associated benefits. Employment and education are likely to increase income and thus facilitate more expenditure on exercise. But the time cost of exercise is also likely to increase, meaning that the impact on demand is ambiguous. The study uses data from a trial of self-management support that included people with diabetes, COPD or IBS. EQ-5D, self-assessed health and the amount of time spent ‘being happy’ were all collected. Information was available for 12 different self-management activities, including ‘do exercises’ and ‘rest and relax’, and the extent to which individuals did these. Outcomes for 3,472 people at 12-month follow-up are estimated, controlling for outcomes at baseline and 6 months. The study assumes that employment and education affect health via their influence on exercise and relaxation. That seems a bit questionable and the other 10 self-management indicators could have been looked at to test this. People in full-time employment were 11 percentage points less likely to use relaxation to manage their condition, suggesting that the substitution effect on time dominates as the opportunity cost of self-management increases. Having a degree or professional qualification increased the probability of using exercise by 5 percentage points, suggesting that the income effect dominates. Those who are more likely to use either exercise or relaxation are also more likely to do the other. An interesting suggestion is that time preference might explain things here. Those with more education may prefer to exercise (as an investment) than to get the instant gratification of rest and relaxation. It’s important that policy recommendations take into consideration the fact that different groups will respond differently to incentives for self-management, at least partly due to their differing time constraints. The thing I find most interesting is the analysis of the different outcomes (something I’ve worked on). Exercise is found to improve self-assessed health, while relaxation increases happiness. Neither exercise or relaxation had a (statistically significant) effect on EQ-5D. Depending on your perspective, this either suggests that the EQ-5D is failing to identify important changes in broad health-related domains or it means that self-management does not achieve the goals (QALYs to the max) of the health service.

New findings from the time trade-off for income approach to elicit willingness to pay for a quality adjusted life year. The European Journal of Health Economics [PubMedPublished 8th March 2017

The question ‘what is a QALY worth’ could invoke any number of reactions in a health economist, from chin scratching to eye rolling. The perspective that we’re probably most familiar with in the UK is that the value of a QALY is the value of health foregone in order to achieve it (i.e. opportunity cost within the health care perspective). An alternative perspective is that the value of a QALY is the consumption value of health; how much consumption would individuals be willing to give up in order to obtain an additional QALY? This second perspective facilitates a broader societal perspective. It can tell us whether or not the budget is set at an appropriate level, while the health care perspective can only take the budget as given. This study relates mainly to decisions made with the ‘consumption value’ perspective. One approach that has been proposed is to assess willingness to pay for a QALY using a time trade-off exercise that incorporates trade-offs between length and quality of life and income. This study builds on the original work by using a multiplicative utility function to estimate willingness to pay and also bringing in prospect theory to allow for reference dependence and loss aversion. 550 participants were asked to choose between living 10 years in their current health state with their current salary or to live a reduced number of years in their current health state with a luxury income (pre-specified by the participant). Respondents were also asked to make a similar choice, but framed as a loss of income, between living 10 years at a subsistence income or fewer years with their current income. A quality of life trade-off exercise was also conducted, in which people traded reduced health and a lower income. The findings support the predictions of prospect theory. Loss aversion is found to be stronger for duration than for quality of life. Individuals were more willing to sacrifice life years to move from subsistence income to current income than to move from current income to luxury income. The results imply that quality of life and income are closer substitutes than longevity and income. That makes sense, given the all-or-nothing nature of being alive. Crucially, the findings highlight the need to better understand the shape of the underlying lifetime utility function. In all tasks, more than half of respondents were either non-traders or over-traded, indicating a negative willingness to pay. That should give pause for thought when it comes to any aggregation of the results. Willingness to pay studies often throw up more questions than answers. This one does so more than most, particularly about sources of bias in people’s responses. The authors identify plenty of opportunities for future research.

Beyond QALYs: multi-criteria based estimation of maximum willingness to pay for health technologies. The European Journal of Health Economics [PubMed] Published 3rd March 2017

Life is messy. Evaluating things in terms of a single outcome, whether that be QALYs, £££s or whatever, is necessarily simplifying and restrictive. That’s not necessarily a bad thing, but we’d do well to bear it in mind. In this paper, Erik Nord sets out a kind of cost value analysis that does away with QALYs (gasp!). The author starts by outlining some familiar criticisms of the QALY approach, such as its failure to consider the inherent value of life and people’s differing reference points. Generally, I see these as features rather than bugs, and it isn’t QALYs themselves in the crosshairs here so much as cost-per-QALY analysis. The proposed method flips current practice by putting societal preferences about fair and efficient resource allocation before attaching values to the outcomes. As such, it acknowledges the fact that society’s preferences for gains in quality of life differ from those for gains in length of life. For example, society may prefer treating the more severely ill (independent of age) but also exhibit a ‘fair innings’ preference that is related to age. Thus, quality and quantity of life are disaggregated and the QALY is no more. A set of tables is presented that can be read to assess ‘value’ in alternative scenarios, given the assumptions set out in the paper. There is merit in the approach and a lot that I like about the possibilities of its use. But for me, the whole thing was made less attractive by the way it is presented in the paper. The author touts willingness to pay – for quality of life gains and for longevity gains – as the basis for value. Anything that makes resource allocation more dependent on willingness to pay values for things without a price (health, life) is a big no-no for me. But the method doesn’t depend on that. Furthermore, as is so often the case, most of the criticisms within relate to ways of using QALYs, rather than the fundamental basis for their estimation. This only weakens the argument for an alternative. But I can think of plenty of problems with QALYs, some of which might be addressed by this alternative approach. It’s unfortunate that the paper doesn’t outline how these more fundamental problems might be addressed. There may come a day when we do away with QALYs, and we may end up doing something similar to what’s outlined here, but we need to think harder about how this alternative is really better.

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Chris Sampson’s journal round-up for 6th February 2017

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 review of NICE methods and processes across health technology assessment programmes: why the differences and what is the impact? Applied Health Economics and Health Policy [PubMed] Published 27th January 2017

Depending on the type of technology under consideration, NICE adopts a variety of different approaches in coming up with their recommendations. Different approaches might result in different decisions, which could undermine allocative efficiency. This study explores this possibility. Data were extracted from the manuals and websites for 5 programmes, under the themes of ‘remit and scope’, ‘process of assessment’, ‘methods of evaluation’ and ‘appraisal of evidence’. Semi-structured interviews were conducted with 5 people with expertise in each of the 5 programmes. Results are presented in a series of tables – one for each theme – outlining the essential characteristics of the 5 programmes. In their discussion, the authors then go on to consider how the identified differences might impact on efficiency from either a ‘utilitarian’ health-maximisation perspective or NICE’s egalitarian aim of ensuring adequate levels of health care. Not all programmes deliver recommendations with mandatory funding status, and it is only the ones that do that have a formal appeals process. Allowing for local rulings on funding could be good or bad news for efficiency, depending on the capacity of local decision makers to conduct economic evaluations (so that means probably bad news). At the same time, regional variation could undermine NICE’s fairness agenda. The evidence considered by the programmes varies, from a narrow focus on clinical and cost-effectiveness to the incorporation of budget impact and wider ethical and social values. Only some of the programmes have reference cases, and those that do are the ones that use cost-per-QALY analysis, which probably isn’t a coincidence. The fact that some programmes use outcomes other than QALYs obviously has the potential to undermine health-maximisation. Most differences or borne of practicality; there’s no point in insisting on a CUA if there is no evidence at all to support one – the appraisal would simply not happen. The very existence of alternative programmes indicates that NICE is not simply concerned with health-maximisation. Additional weight is given to rare conditions, for example. And NICE want to encourage research and innovation. So it’s no surprise that we need to take into account NICE’s egalitarian view to understand the type of efficiency for which it strives.

Economic evaluations alongside efficient study designs using large observational datasets: the PLEASANT trial case study. PharmacoEconomics [PubMed] Published 21st January 2017

One of the worst things about working on trial-based economic evaluations is going to lots of effort to collect lots of data, then finding that at the end of the day you don’t have much to show for it. Nowadays, the health service routinely collects many data for other purposes. There have been proposals to use these data – instead of prospectively collecting data – to conduct clinical trials. This study explores the potential for doing an economic evaluation alongside such a trial. The study uses CPRD data, including diagnostic, clinical and resource use information, for 8,608 trial participants. The intervention was the sending out of a letter in the hope of reducing unscheduled medical contacts due to asthma exacerbation in children starting a new school year. QALYs couldn’t be estimated using the CPRD data, so values were derived from the literature and estimated on the basis of exacerbations indicated by changes in prescriptions or hospitalisations. Note here the potentially artificial correlation between costs and outcomes that this creates, thus somewhat undermining the benefit of some good old bootstrapping. The results suggest the intervention is cost-saving with little impact on QALYs. Lots of sensitivity analyses are conducted, which are interesting in themselves and say something about the concerns around some of the structural assumptions. The authors outline the pros and cons of the approach. It’s an important discussion as it seems that studies like this are going to become increasingly common. Regarding data collection, there’s little doubt that this approach is more efficient, and it should be particularly valuable in the evaluation of public health and service delivery type interventions. The problem is that the study is not able to use individual-level cost and outcome data from the same people, which is what sets a trial-based economic evaluation apart from a model-based study. So for me, this isn’t really a trial-based economic evaluation. Indeed, the analysis incorporates a Markov-type model of exacerbations. It’s a different kind of beast, which incorporates aspects of modelling and aspects of trial-based analysis, along with some unique challenges of its own. There’s a lot more methodological work that needs to be done in this area, but this study demonstrates that it could be fruitful.

“Too much medicine”: insights and explanations from economic theory and research. Social Science & Medicine [PubMed] Published 18th January 2017

Overconsumption of health care represents an inefficient use of resources, and so we wouldn’t recommend it. But is that all we – as economists – have to say on the matter? This study sought to dig a little deeper. A literature search was conducted to establish a working definition of overconsumption. Related notions such as overdiagnosis, overtreatment, overuse, low-value care, overmedicalisation and even ‘pharmaceuticalisation’ all crop up. The authors introduce ‘need’ as a basis for understanding overconsumption; it represents health care that should never be considered as “needed”. A useful distinction is identified between misconsumption – where an individual’s own consumption is detrimental to their own well-being – and overconsumption, which can be understood as having a negative effect on social welfare. Note that in a collectively funded system the two concepts aren’t entirely distinguishable. Misconsumption becomes the focus of the paper, as avoiding harm to patients has been the subject of the “too much medicine” movement. I think this is a shame, and not really consistent with an economist’s usual perspective. The authors go on to discuss issues such as moral hazard, supplier-induced demand, provider payment mechanisms, ‘indication creep’, regret theory, and physicians’ positional consumption, and whether or not such phenomena might lead to individual welfare losses and thus be considered causes of misconsumption. The authors provide a neat diagram showing the various causes of misconsumption on a plane. One dimension represents the extent to which the cause is imperfect knowledge or imperfect agency, and the other the degree to which the cause is at the individual or market level. There’s a big gap in the top right, where market level causes meet imperfect knowledge. This area could have included patent systems, research fraud and dodgy Pharma practices. Or maybe just a portrait of Ben Goldacre for shorthand. There are some warnings about the (limited) extent to which market reforms might address misconsumption, and the proposed remedy for overconsumption is not really an economic one. Rather, a change in culture is prescribed. More research looking at existing treatments rather than technology adoption, and to investigate subgroup effects, is also recommended. The authors further suggest collaboration between health economists and ecological economists.

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Paul Mitchell’s journal round-up for 2nd January 2017

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.

Age effects in mortality risk valuation. European Journal of Health Economics [PubMed] [RePEcPublished 7th December 2016

Placing values on statistical life years has important public policy implications in measuring who benefits and how much they benefit from interventions. The authors of this study provide what they describe as the most comprehensive evidence to date against a constant value for a statistical life year, an assumption they argue is also applicable when calculating QALYs. Using a Spanish household survey collected over a large sample size (approximately 6,000 individuals), the authors study the relationship between willingness to pay (WTP) and age, by estimating individual WTP for reduction in risk of mortality due to acute myocardial infarction. Three different WTP elicitation procedures were performed. Parametric, semi-nonparametric and non-parametric models using marginal and total approaches were applied to understand the relationship using many alternative methods. Binary variables for income (proxied on a measure of self-perceived social status), education (>lower secondary level) and gender were also included as controls for the models. The results of the linear model show that WTP is lower as age increases. Those with higher income (i.e. social status) and education have higher WTP, while gender is not significant in any model. Sensitivity tests were as hypothesised. The non-parametric model produces similar results to the others, albeit with a higher senior discount. The senior discount is not independent of the income variable. From this, the authors estimate the value of a statistical life year for an 85 year old to be 3.5 times higher than that of a 20 year old. The authors are keen to highlight the strengths of their findings with a large sample size allowing for the robustness of results to be tested across a number of different model types. However, they do flag up the lack of comparability with previous studies that have focused on risk reductions with a lower probability of mortality. The assumption that the authors make that their findings for life years have direct applicability for QALYs is somewhat questionable, particularly for non-acute conditions and QALYs calculated for them. The rationale behind the three types of preference elicitation methods and how/why they were chosen is not apparent in the paper itself. The social status measure they use as a proxy for income is also questionable, and appeared to be applied to maximise sample size. If data for real income was used or imputation of income was included for missing data, it would be interesting to see what impact this may have had on their study findings.

Preferences for public involvement in health service decisions: a comparison between best-worst scaling and trio-wise stated preference elicitation techniques. European Journal of Health Economics [PubMedPublished 10th December 2016

Public involvement in health care is something that has become increasingly recognised as important to do and to be informed by public perspectives when making important decisions for their community. How and where that public involvement should feed into decision making is less well understood. In this study, the authors compare two methods, best worst scaling (BWS) case 2, and a new method the authors call ‘trio-wise’ where the choice task is presented in an equilateral triangle. Using ‘trio-wise’, respondents are able to click in any part of the triangle; this the authors argue gives additional insight on the strength of a respondent’s preferences and also accommodates indifferent preferences. Public preferences are sought using these two methods to understand what aspects of public involvement are most important. Eight general characteristics are included in the exercises. Respondents completed either BWS or the ‘trio-wise’ task (not both) using web based surveys. Approximately 1,700 individuals per arm were sampled. Only three of the eight general characteristics could be completed at any one time due to the trio-wise triangle approach. There was some evidence of position bias for both exercises. The authors say that weak preferences were observed using the trio-wise approach but this could be due to difficulty participants faced in choosing which generic characteristic was more important without further information. Impact and focus of public involvement are found to be the most important characteristics across both BWS and trio-wise. The authors find preference intensity has no bearing on choice probabilities, but this could be an artefact of the weak preferences observed in the sample. Although I can see the appeal of using the trio-wise approach when there are only three characteristics, BWS is advantageous in tasks with more characteristics. Indeed it feels that the findings from this experiment were impeded by the use of the trio-wise approach when much more useful information on guiding future public involvement practice could have been gathered using either BWS or a discrete choice experiment (DCE) across all eight characteristics and the options of public involvement within each characteristic.

How do individuals value health states? A qualitative investigation. Social Science & Medicine [PubMedPublished 22nd November 2016

The valuation tasks of health states used to generate QALYs have been previously found to be complex tasks for members of the general public to complete, who have little experience of such health states. This qualitative study seeks to gain a better understanding as to how the general public complete such tasks. Using a purposive sample, 21 individuals were asked to complete eight DCEs and three TTO tasks, based on the EQ-5D-5L valuation protocol. Participants were asked to complete the valuation tasks using think aloud, followed by semi-structured interviews. Three main themes emerged from the framework analysis undertaken on the interview transcripts. Firstly, individuals had to interpret a health state, using their imagination and experience to help visualise a realistic health state with those problems. Knowledge, understanding of descriptive system, additional information for a health state, re-writing of health states and problems with EQ-5D labels all impacted this process. The second theme was called conversion factors, which the authors took to mean in this context the personal and social factors that affected how participants valued health states. Personal interests, values and circumstances were said to have an effect on the interpretation of a health state. The final theme was based on the consequences of health states, that tended to focus on non-health effects caused by health problems, such as activities, enjoyment, independence, relationships, dignity and avoiding being a burden. The authors subsequently developed a three-stage explanatory account as to how people valued health states based on the interview findings. Although I would have some concerns about the generalisability of these findings to general public valuation studies, given the highly educated sample, it does highlight some issues about what health economists might implicitly think individuals are doing when completing such tasks compared to what they actually are doing. There are clearly problems for individuals completing such hypothetical health states, with the authors suggesting a more reflective and deliberative approach to overcome such problems. The authors also raise an interesting comment as to whether participants actually do weigh the consequences of health states and follow compensatory decision-making or instead are using simplifying heuristics based on one attribute, which I agree is an area that requires further investigation.

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