Chris Sampson’s journal round-up for 2nd December 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.

The treatment decision under uncertainty: the effects of health, wealth and the probability of death. Journal of Health Economics Published 16th November 2019

It’s important to understand how people make decisions about treatment. At the end of life, the question can become a matter of whether to have treatment or to let things take their course such that you end up dead. In order to consider this scenario, the author of this paper introduces the probability of death to some existing theoretical models of decision-making under uncertainty.

The diagnostic risk model and the therapeutic risk model can be used to identify risk thresholds that determine decisions about treatment. The diagnostic model relates to the probability that disease is present and the therapeutic model relates to the probability that treatment is successful. The new model described in this paper builds on these models to consider the impact on the decision thresholds of i) initial health state, ii) probability of death, and iii) wealth. The model includes wealth after death, in the form of a bequest. Limited versions of the model are also considered, excluding the bequest and excluding wealth (described as a ‘QALY model’). Both an individual perspective and an aggregate perspective are considered by excluding and including the monetary cost of diagnosis and treatment, to allow for a social insurance type setting.

The comparative statics show a lot of ambiguity, but there are a few things that the model can tell us. The author identifies treatment as having an ‘insurance effect’, by reducing diagnostic risk, a ‘protective effect’, by lowering the probability of death, and a risk-increasing effect associated with therapeutic risk. A higher probability of death increases the propensity for treatment in both the no-bequest model and the QALY model, because of the protective effect of treatment. In the bequest model, the impact is ambiguous, because treatment costs reduce the bequest. In the full model, wealthier individuals will choose to undergo treatment at a lower probability of success because of a higher marginal utility for survival, but the effect becomes ambiguous if the marginal utility of wealth depends on health (which it obviously does).

I am no theoretician, so it can take me a long time to figure these things out in my head. For now, I’m not convinced that it is meaningful to consider death in this way using a one-period life model. In my view, the very definition of death is a loss of time, which plays little or no part in this model. But I think my main bugbear is the idea that anybody’s decision about life saving treatment is partly determined by the amount of money they will leave behind. I find this hard to believe. The author links the finding that a higher probability of death increases treatment propensity to NICE’s end of life premium. Though I’m not convinced that the model has anything to do with NICE’s reasoning on this matter.

Moving toward evidence-based policy: the value of randomization for program and policy implementation. JAMA [PubMed] Published 15th November 2019

Evidence-based policy is a nice idea. We should figure out whether something works before rolling it out. But decision-makers (especially politicians) tend not to think in this way, because doing something is usually seen to be better than doing nothing. The authors of this paper argue that randomisation is the key to understanding whether a particular policy creates value.

Without evidence based on random allocation, it’s difficult to know whether a policy works. This, the authors argue, can undermine the success of effective interventions and allow harmful policies to persist. A variety of positive examples are provided from US healthcare, including trials of Medicare bundled payments. Apparently, such trials increased confidence in the programmes’ effects in a way that post hoc evaluations cannot, though no evidence of this increased confidence is actually provided. Policy evaluation is not always easy, so the authors describe four preconditions for the success of such studies: i) early engagement with policymakers, ii) willingness from policy leaders to support randomisation, iii) timing the evaluation in line with policymakers’ objectives, and iv) designing the evaluation in line with the realities of policy implementation.

These are sensible suggestions, but it is not clear why the authors focus on randomisation. The paper doesn’t do what it says on the tin, i.e. describe the value of randomisation. Rather, it explains the value of pre-specified policy evaluations. Randomisation may or may not deserve special treatment compared with other analytical tools, but this paper provides no explanation for why it should. The authors also suggest that people are becoming more comfortable with randomisation, as large companies employ experimental methods, particularly on the Internet with A/B testing. I think this perception is way off and that most people feel creeped out knowing that the likes of Facebook are experimenting on them without any informed consent. In the authors’ view, it being possible to randomise is a sufficient basis on which to randomise. But, considering the ethics, as well as possible methodological contraindications, it isn’t clear that randomisation should become the default.

A new tool for creating personal and social EQ-5D-5L value sets, including valuing ‘dead’. Social Science & Medicine Published 30th November 2019

Nobody can agree on the best methods for health state valuation. Or, at least, some people have disagreed loud enough to make it seem that way. Novel approaches to health state valuation are therefore welcome. Even more welcome is the development and testing of methods that you can try at home.

This paper describes the PAPRIKA method (Potentially All Pairwise RanKings of all possible Alternatives) of discrete choice experiment, implemented using 1000Minds software. Participants are presented with two health states that are defined in terms of just two dimensions, each lasting for 10 years, and asked to choose between them. Using the magical power of computers, an adaptive process identifies further choices, automatically ranking states using transitivity so that people don’t need to complete unnecessary tasks. In order to identify where ‘dead’ sits on the scale, a binary search procedure asks participants to compare EQ-5D states with being dead. What’s especially cool about this process is that everybody who completes it is able to view their own personal value set. These personal value sets can then be averaged to identify a social value set.

The authors used their tool to develop an EQ-5D-5L value set for New Zealand (which is where the researchers are based). They recruited 5,112 people in an online panel, such that the sample was representative of the general public. Participants answered 20 DCE questions each, on average, and almost half of them said that they found the questions difficult to answer. The NZ value set showed that anxiety/depression was associated with the greatest disutility, though each dimension has a notably similar level of impact at each level. The value set correlates well with numerous existing value sets.

The main limitation of this research seems to be that only levels 1, 3, and 5 of each EQ-5D-5L domain were included. Including levels 2 and 4 would more than double the number of questions that would need to be answered. It is also concerning that more than half of the sample was excluded due to low data quality. But the authors do a pretty good job of convincing us that this is for the best. Adaptive designs of this kind could be the future of health state valuation, especially if they can be implemented online, at low cost. I expect we’ll be seeing plenty more from PAPRIKA.

Credits

Chris Sampson’s journal round-up for 18th November 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 conceptual map of health-related quality of life dimensions: key lessons for a new instrument. Quality of Life Research [PubMed] Published 1st November 2019

EQ-5D, SF-6D, HUI3, AQoL, 15D; they’re all used to describe health states for the purpose of estimating health state utility values, to get the ‘Q’ in the QALY. But it’s widely recognised (and evidenced) that they measure different things. This study sought to better understand the challenge by doing two things: i) ‘mapping’ the domains of the different instruments and ii) advising on the domains to be included in a new measure.

The conceptual model described in this paper builds on two standard models of health – the ICF (International Classification of Functioning, Disability, and Health), which is endorsed by the WHO, and the Wilson and Cleary model. The new model is built around four distinctions, which can be used to define the dimensions included in health state utility instruments: cause vs effect, specific vs broad, physical vs psychological, and subjective vs objective. The idea is that each possible dimension of health can relate, with varying levels of precision, to one or the other of these alternatives.

The authors argue that, conveniently, cause/effect and specific/broad map to one another, as do physical/psychological and objective/subjective. The framework is presented visually, which makes it easy to interpret – I recommend you take a look. Each of the five instruments previously mentioned is mapped to the framework, with the HUI and 15D coming out as ‘symptom’ oriented, EQ-5D and SF-6D as ‘functioning’ oriented, and the AQoL as a hybrid of a health and well-being instrument. Based (it seems) on the Personal Wellbeing Index, the authors also include two social dimensions in the framework, which interact with the health domains. Based on the frequency with which dimensions are included in existing instruments, the authors recommend that a new measure should include three physical dimensions (mobility, self-care, pain), three mental health dimensions (depression, vitality, sleep), and two social domains (personal relationships, social isolation).

This framework makes no sense to me. The main problem is that none of the four distinctions hold water, let alone stand up to being mapped linearly to one another. Take pain as an example. It could be measured subjectively or objectively. It’s usually considered a physical matter, but psychological pain is no less meaningful. It may be a ‘causal’ symptom, but there is little doubt that it matters in and of itself as an ‘effect’. The authors themselves even offer up a series of examples of where the distinctions fall down.

It would be nice if this stuff could be drawn-up on a two-dimensional plane, but it isn’t that simple. In addition to oversimplifying complex ideas, I don’t think the authors have fully recognised the level of complexity. For instance, the work seems to be inspired – at least in part – by a desire to describe health state utility instruments in relation to subjective well-being (SWB). But the distinction between health state utility instruments and SWB isn’t simply a matter of scope. Health state utility instruments (as we use them) are about valuing states in relation to preferences, whereas SWB is about experienced utility. That’s a far more important and meaningful distinction than the distinction between symptoms and functioning.

Careless costs related to inefficient technology used within NHS England. Clinical Medicine Journal [PubMed] Published 8th November 2019

This little paper – barely even a single page – was doing the rounds on Twitter. The author was inspired by some frustration in his day job, waiting for the IT to work. We can all relate to that. This brief analysis sums the potential costs of what the author calls ‘careless costs’, which is vaguely defined as time spent by an NHS employee on activity that does not relate to patient care. Supposing that all doctors in the English NHS wasted an average of 10 minutes per day on such activities, it would cost over £143 million (per year, I assume) based on current salaries. The implication is that a little bit of investment could result in massive savings.

This really bugs me, for at least two reasons. First, it is normal for anybody in any profession to have a bit of downtime. Nobody operates at maximum productivity for every minute of every day. If the doctor didn’t have their downtime waiting for a PC to boot, it would be spent queuing in Costa, or having a nice relaxed wee. Probably both. Those 10 minutes that are displaced cannot be considered equivalent in value to 10 minutes of patient contact time. The second reason is that there is no intervention that can fix this problem at little or no cost. Investments cost money. And if perfect IT systems existed, we wouldn’t all find these ‘careless costs’ so familiar. No doubt, the NHS lags behind, but the potential savings of improvement may very well be closer to zero than to the estimates in this paper.

When it comes to clinical impacts, people insist on being able to identify causal improvements from clearly defined interventions or changes. But when it comes to costs, too many people are confident in throwing around huge numbers of speculative origin.

Socioeconomic disparities in unmet need for student mental health services in higher education. Applied Health Economics and Health Policy [PubMed] Published 5th November 2019

In many countries, the size of the student population is growing, and this population seems to have a high level of need for mental health services. There are a variety of challenges in this context that make it an interesting subject for health economists to study (which is why I do), including the fact that universities are often the main providers of services. If universities are going to provide the right services and reach the right people, a better understanding of who needs what is required. This study contributes to this challenge.

The study is set in the context of higher education in Ireland. If you have no idea how higher education is organised in Ireland, and have an interest in mental health, then the Institutional Context section of this paper is worth reading in its own right. The study reports on findings from a national survey of students. This analysis is a secondary analysis of data collected for the primary purpose of eliciting students’ preferences for counselling services, which has been described elsewhere. In this paper, the authors report on supplementary questions, including measures of psychological distress and use of mental health services. Responses from 5,031 individuals, broadly representative of the population, were analysed.

Around 23% of respondents were classified as having unmet need for mental health services based on them reporting both a) severe distress and b) not using services. Arguably, it’s a sketchy definition of unmet need, but it seems reasonable for the purpose of this analysis. The authors regress this binary indicator of unmet need on a selection of sociodemographic and individual characteristics. The model is also run for the binary indicator of need only (rather than unmet need).

The main finding is that people from lower social classes are more likely to have unmet need, but that this is only because these people have a higher level of need. That is, people from less well-off backgrounds are more likely to have mental health problems but are no less likely to have their need met. So this is partly good news and partly bad news. It seems that there are no additional barriers to services in Ireland for students from a lower social class. But unmet need is still high and – with more inclusive university admissions – likely to grow. Based on the analyses, the authors recommend that universities could reach out to male students, who have greater unmet need.

Credits

Chris Sampson’s journal round-up for 28th October 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.

Spatial competition and quality: evidence from the English family doctor market. Journal of Health Economics [RePEc] Published 17th October 2019

Researchers will never stop asking questions about the role of competition in health care. There’s a substantial body of literature now suggesting that greater competition in the context of regulated prices may bring some quality benefits. But with weak indicators of quality and limited generalisability, it isn’t a closed case. One context in which evidence has been lacking is in health care beyond the hospital. In the NHS, an individual’s choice of GP practice is perhaps the context in which quality can be observed and choice most readily (and meaningfully) exercised. That’s where this study comes in. Aside from the horrible format of a ‘proper economics’ paper (where we start with spoilers and climax with robustness tests), it’s a good read.

The study relies on a measure of competition based on the number of rival GPs within a 2km radius. Number of GPs, that is, rather than number of practices. This is important, as the number of GPs per practice has been increasing. About 75% of a practice’s revenues are linked to the number of patients registered, wherein lies the incentive to compete with other practices for patients. And, in this context, research has shown that patient choice is responsive to indicators of quality. The study uses data for 2005-2012 from all GP practices in England, making it an impressive data set.

The measures of quality come from the Quality and Outcomes Framework (QOF) and the General Practice Patient Survey (GPPS) – the former providing indicators of clinical quality and the latter providing indicators of patient experience. A series of OLS regressions are run on the different outcome measures, with practice fixed effects and various characteristics of the population. The models show that all of the quality indicators are improved by greater competition, but the effect is very small. For example, an extra competing GP within a 2km radius results in 0.035% increase in the percentage of the population for whom the QOF indicators have been achieved. The effects are a little stronger for the patient satisfaction indicators.

The paper reports a bunch of important robustness checks. For instance, the authors try to test whether practices select their locations based on the patient casemix, finding no evidence that they do. The authors even go so far as to test the impact of a policy change, which resulted in an exogenous increase in the number of GPs in some areas but not others. The main findings seem to have withstood all the tests. They also try out a lagged model, which gives similar results.

The findings from this study slot in comfortably with the existing body of research on the role of competition in the NHS. More competition might help to achieve quality improvement, but it hardly seems worthy of dedicating much effort or, importantly, much expense to the cause.

Worth living or worth dying? The views of the general public about allowing disabled children to die. Journal of Medical Ethics [PhilPapers] [PubMed] Published 15th October 2019

Recent years have seen a series of cases in the UK where (usually very young) children have been so unwell and with such a severe prognosis that someone (usually a physician) has judged that continued treatment is not warranted and that the child should be allowed to die. These cases have generated debate and outrage in the media. But what do people actually think?

This study recruited members of the public in the UK (n=130) to an online panel and asked about the decisions that participants would support. The survey had three parts. The first part set out six scenarios of hospitalised infants, which varied in terms of the infants’ physical and sensory abilities, cognitive capacity, level of suffering, and future prospects. Some of the cases approximated real cases that have received media coverage, and the participants were asked whether they thought that withdrawing treatment was justified in each case. In the second part of the survey, participants were asked about the factors that they believed were important in making such decisions. In the third part, participants answered a few questions about themselves and answered the Oxford Utilitarianism Scale.

The authors set up the concept of a ‘life not worth living’, based on the idea that net future well-being is ‘negative’, and supposing the individual’s own judgement were they able to provide it. In the first part of the survey, 88% indicated that life would be worse than death in at least one of the cases. In such cases, 65% thought that treatment withdrawal was ethically obligatory, while 33% thought that either decision was acceptable. Pain was considered the most important factor in making such decisions, followed by the presence of pleasure. Perhaps predictably for health economists familiar with the literature, about 42% of people thought that resources should be considered in the decision, while 40% thought they shouldn’t.

The paper includes an extensive discussion, with plenty of food for thought. In particular, it discusses the ways in which the findings might inform the debate between the ‘zero line view’, whereby treatment should be withdrawn at the point where life has no benefit, and the ‘threshold view’, which establishes a grey zone of ethical uncertainty, in which either decision is ethically acceptable. To some extent, the findings of this study support the need for a threshold approach. Ethical questions are rarely black and white.

How is the trade-off between adverse selection and discrimination risk affected by genetic testing? Theory and experiment. Journal of Health Economics [PubMed] [RePEc] Published 1st October 2019

A lot of people are worried about how knowledge of their genetic information could be used against them. The most obvious scenario is one in which insurers increase premiums – or deny coverage altogether – on the basis of genetic risk factors. There are two key regulatory options in this context – disclosure duty, whereby individuals are obliged to tell insurers about the outcome of genetic tests, or consent law, whereby people can keep the findings to themselves. This study explores how people behave under each of these regulations.

The authors set up a theoretical model in which individuals can choose whether to purchase a genetic test that can identify them as being either high-risk or low-risk of developing some generic illness. The authors outline utility functions under disclosure duty and consent law. Under disclosure duty, individuals face a choice between the certainty of not knowing their risk and receiving pooled insurance premiums, or a lottery in which they have to disclose their level of risk and receive a higher or lower premium accordingly. Under consent law, individuals will only reveal their test results if they are at low risk, thus securing lower premiums and contributing to adverse selection. As a result, individuals will be more willing to take a test under consent law than under disclosure duty, all else equal.

After setting out their model (at great length), the authors go on to describe an experiment that they conducted with 67 economics students, to elicit preferences within and between the different regulatory settings. The experiment was set up in a very generic way, not related to health at all. Participants were presented with a series of tasks across which the parameters representing the price of the test and the pooled premium were varied. All of the authors’ hypotheses were supported by the experiment. More people took tests under consent law. Higher test prices reduce the number of people taking tests. If prices are high enough, people will prefer disclosure duty. The likelihood that people take tests under consent law is increasing with the level of adverse selection. And people are very sensitive to the level of discrimination risk under disclosure duty.

It’s an interesting study, but I’m not sure how much it can tell us about genetic testing. Framing the experiment as entirely unrelated to health seems especially unwise. People’s risk preferences may be very different in the domain of real health than in the hypothetical monetary domain. In the real world, there’s a lot more at stake.

Credits