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.

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Sam Watson’s journal round-up for 11th February 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.

Contest models highlight inherent inefficiencies of scientific funding competitions. PLoS Biology [PubMed] Published 2nd January 2019

If you work in research you will have no doubt thought to yourself at one point that you spend more time applying to do research than actually doing it. You can spend weeks working on (what you believe to be) a strong proposal only for it to fail against other strong bids. That time could have been spent collecting and analysing data. Indeed, the opportunity cost of writing extensive proposals can be very high. The question arises as to whether there is another method of allocating research funding that reduces this waste and inefficiency. This paper compares the proposal competition to a partial lottery. In this lottery system, proposals are short, and among those that meet some qualifying standard those that are funded are selected at random. This system has the benefit of not taking up too much time but has the cost of reducing the average scientific value of the winning proposals. The authors compare the two approaches using an economic model of contests, which takes into account factors like proposal strength, public benefits, benefits to the scientist like reputation and prestige, and scientific value. Ultimately they conclude that, when the number of awards is smaller than the number of proposals worthy of funding, the proposal competition is inescapably inefficient. It means that researchers have to invest heavily to get a good project funded, and even if it is good enough it may still not get funded. The stiffer the competition the more researchers have to work to win the award. And what little evidence there is suggests that the format of the application makes little difference to the amount of time spent by researchers on writing it. The lottery mechanism only requires the researcher to propose something that is good enough to get into the lottery. Far less time would therefore be devoted to writing it and more time spent on actual science. I’m all for it!

Preventability of early versus late hospital readmissions in a national cohort of general medicine patients. Annals of Internal Medicine [PubMed] Published 5th June 2018

Hospital quality is hard to judge. We’ve discussed on this blog before the pitfalls of using measures such as adjusted mortality differences for this purpose. Just because a hospital has higher than expected mortality does not mean those death could have been prevented with higher quality care. More thorough methods assess errors and preventable harm in care. Case note review studies have suggested as little as 5% of deaths might be preventable in England and Wales. Another paper we have covered previously suggests then that the predictive value of standardised mortality ratios for preventable deaths may be less than 10%.

Another commonly used metric is readmission rates. Poor care can mean patients have to return to the hospital. But again, the question remains as to how preventable these readmissions are. Indeed, there may also be substantial differences between those patients who are readmitted shortly after discharge and those for whom it may take a longer time. This article explores the preventability of early and late readmissions in ten hospitals in the US. It uses case note review and a number of reviewers to evaluate preventability. The headline figures are that 36% of early readmissions are considered preventable compared to 23% of late readmissions. Moreover, it was considered that the early readmissions were most likely to have been preventable at the hospital whereas for late readmissions, an outpatient clinic or the home would have had more impact. All in all, another paper which provides evidence to suggest crude, or even adjusted rates, are not good indicators of hospital quality.

Visualisation in Bayesian workflow. Journal of the Royal Statistical Society: Series A (Statistics in Society) [RePEc] Published 15th January 2019

This article stems from a broader programme of work from these authors on good “Bayesian workflow”. That is to say, if we’re taking a Bayesian approach to analysing data, what steps ought we to be taking to ensure our analyses are as robust and reliable as possible? I’ve been following this work for a while as this type of pragmatic advice is invaluable. I’ve often read empirical papers where the authors have chosen, say, a logistic regression model with covariates x, y, and z and reported the outcomes, but at no point ever justified why this particular model might be any good at all for these data or the research objective. The key steps of the workflow include, first, exploratory data analysis to help set up a model, and second, performing model checks before estimating model parameters. This latter step is important: one can generate data from a model and set of prior distributions, and if the data that this model generates looks nothing like what we would expect the real data to look like, then clearly the model is not very good. Following this, we should check whether our inference algorithm is doing its job, for example, are the MCMC chains converging? We can also conduct posterior predictive model checks. These have had their criticisms in the literature for using the same data to both estimate and check the model which could lead to the model generalising poorly to new data. Indeed in a recent paper of my own, posterior predictive checks showed poor fit of a model to my data and that a more complex alternative was better fitting. But other model fit statistics, which penalise numbers of parameters, led to the alternative conclusions. So the simpler model was preferred on the grounds that the more complex model was overfitting the data. So I would argue posterior predictive model checks are a sensible test to perform but must be interpreted carefully as one step among many. Finally, we can compare models using tools like cross-validation.

This article discusses the use of visualisation to aid in this workflow. They use the running example of building a model to estimate exposure to small particulate matter from air pollution across the world. Plots are produced for each of the steps and show just how bad some models can be and how we can refine our model step by step to arrive at a convincing analysis. I agree wholeheartedly with the authors when they write, “Visualization is probably the most important tool in an applied statistician’s toolbox and is an important complement to quantitative statistical procedures.”

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

Patient choice and provider competition – quality enhancing drivers in primary care? Social Science & Medicine Published 29th January 2019

There’s no shortage of studies in economics claiming to identify the impact (or lack of impact) of competition in the market for health care. The evidence has brought us close to a consensus that greater competition might improve quality, so long as providers don’t compete on price. However, many of these studies aren’t able to demonstrate the mechanism through which competition might improve quality, and the causality is therefore speculative. The research reported in this article was an attempt to see whether the supposed mechanisms for quality improvement actually exist. The authors distinguish between the demand-side mechanisms of competition-increasing quality-improving reforms (i.e. changes in patient behaviour) and the supply-side mechanisms (i.e. changes in provider behaviour), asserting that the supply-side has been neglected in the research.

The study is based on primary care in Sweden’s two largest cities, where patients can choose their primary care practice, which could be a private provider. Key is the fact that patients can switch between providers as often as they like, and with fewer barriers to doing so than in the UK. Prospective patients have access to some published quality indicators. With the goal of maximum variation, the researchers recruited 13 primary health care providers for semi-structured interviews with the practice manager and (in most cases) one or more of the practice GPs. The interview protocol included questions about the organisation of patient visits, information received about patients’ choices, market situation, reimbursement, and working conditions. Interview transcripts were coded and a framework established. Two overarching themes were ‘local market conditions’ and ‘feedback from patient choice’.

Most interviewees did not see competitors in the local market as a threat – conversely, providers are encouraged to cooperate on matters such as public health. Where providers did talk about competing, it was in terms of (speed of) access for patients, or in competition to recruit and keep staff. None of the interviewees were automatically informed of patients being removed from their list, and some managers reported difficulties in actually knowing which patients on their list were still genuinely on it. Even where these data were more readily available, nobody had access to information on reasons for patients leaving. Managers saw greater availability of this information as useful for quality improvement, while GPs tended to think it could be useful in ensuring continuity of care. Still, most expressed no desire to expand their market share. Managers reported using marketing efforts in response to greater competition generally, rather than as a response to observed changes within their practice. But most relied on reputation. Some reported becoming more service-minded as a result of choice reforms.

It seems that practices need more information to be able to act on competitive pressures. But, most practices don’t care about it because they don’t want to expand and they face no risk of there being a shortage of patients (in cities, at least). And, even if they did want to act on the information, chances are it would just create an opportunity for them to improve access as a way of cherry-picking younger and healthier people who demand convenience. Primary care providers (in this study, at least) are not income maximisers, but satisficers (they want to break-even), so there isn’t much scope for reforms to encourage providers to compete for new patients. Patient choice reforms may improve quality, but it isn’t clear that this has anything to do with competitive pressure.

Maximising the impact of patient reported outcome assessment for patients and society. BMJ [PubMed] Published 24th January 2019

Patient-reported outcome measures (PROMs) have been touted as a way of improving patient care. Yet, their use around the world is fragmented. In this paper, the authors make some recommendations about how we might use PROMs to improve patient care. The authors summarise some of the benefits of using PROMs and discuss some of the ways that they’ve been used in the UK.

Five key challenges in the use of PROMs are specified: i) appropriate and consistent selection of the best measures; ii) ethical collection and reporting of PROM data; iii) data collection, analysis, reporting, and interpretation; iv) data logistics; and v) a lack of coordination and efficiency. To address these challenges, the authors recommend an ‘integrated’ approach. To achieve this, stakeholder engagement is important and a governance framework needs to be developed. A handy table of current uses is provided.

I can’t argue with what the paper proposes, but it outlines an idealised scenario rather than any firm and actionable recommendations. What the authors don’t discuss is the fact that the use of PROMs in the UK is flailing. The NHS PROMs programme has been scaled back, measures have been dropped from the QOF, the EQ-5D has been dropped from the GP Patient Survey. Perhaps we need bolder recommendations and new ideas to turn the tide.

Check your checklist: the danger of over- and underestimating the quality of economic evaluations. PharmacoEconomics – Open [PubMed] Published 24th January 2019

This paper outlines the problems associated with misusing methodological and reporting checklists. The author argues that the current number of checklists available in the context of economic evaluation and HTA (13, apparently) is ‘overwhelming’. Three key issues are discussed. First, researchers choose the wrong checklist. A previous review found that the Drummond, CHEC, and Philips checklists were regularly used in the wrong context. Second, checklists can be overinterpreted, resulting in incorrect conclusions. A complete checklist does not mean that a study is perfect, and different features are of varying importance in different studies. Third, checklists are misused, with researchers deciding which items are or aren’t relevant to their study, without guidance.

The author suggests that more guidance is needed and that a checklist for selecting the correct checklist could be the way to go. The issue of updating checklists over time – and who ought to be responsible for this – is also raised.

In general, the tendency seems to be to broaden the scope of general checklists and to develop new checklists for specific methodologies, requiring the application of multiple checklists. As methods develop, they become increasingly specialised and heterogeneous. I think there’s little hope for checklists in this context unless they’re pared down and used as a reminder of the more complex guidance that’s needed to specify suitable methods and achieve adequate reporting. ‘Check your checklist’ is a useful refrain, though I reckon ‘chuck your checklist’ can sometimes be a better strategy.

A systematic review of dimensions evaluating patient experience in chronic illness. Health and Quality of Life Outcomes [PubMed] Published 21st January 2019

Back to PROMs and PRE(xperience)Ms. This study sets out to understand what it is that patient-reported measures are being used to capture in the context of chronic illness. The authors conducted a systematic review, screening 2,375 articles and ultimately including 107 articles that investigated the measurement properties of chronic (physical) illness PROMs and PREMs.

29 questionnaires were about (health-related) quality of life, 19 about functional status or symptoms, 20 on feelings and attitudes about illness, 19 assessing attitudes towards health care, and 20 on patient experience. The authors provide some nice radar charts showing the percentage of questionnaires that included each of 12 dimensions: i) physical, ii) functional, iii) social, iv) psychological, v) illness perceptions, vi) behaviours and coping, vii) effects of treatment, viii) expectations and satisfaction, ix) experience of health care, x) beliefs and adherence to treatment, xi) involvement in health care, and xii) patient’s knowledge.

The study supports the idea that a patient’s lived experience of illness and treatment, and adaptation to that, has been judged to be important in addition to quality of life indicators. The authors recommend that no measure should try to capture everything because there are simply too many concepts that could be included. Rather, researchers should specify the domains of interest and clearly define them for instrument development.

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