Shilpi Swami’s journal round-up for 9th 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.

Performance of UK National Health Service compared with other high-income countries: observational study. BMJ [PubMed] Published 27th November 2019

Efficiencies and inefficiencies of the NHS in the UK have been debated in recent years. This new study reveals the performance of the NHS compared to other high-income countries, based on observational data, and has already caught a bunch of attention (almost 3,000 tweets and 6 news appearances, since publication)!

The authors presented a descriptive analysis of the UK (England, Scotland, Northern Ireland, and Wales) compared to nine other countries (US, Canada, Germany, Australia, Sweden, France, Denmark, the Netherlands, and Switzerland) based on aggregated recent data from a range of sources (such as OECD, World Bank, the Institute for Health Metrics Evaluation, and Eurostat). Good things first; access to care – a lower proportion of people felt unmet needs owing to costs. The waiting times were comparable across other countries, except for specialist care. The UK performed slightly better on the metric of patient safety. The main challenge, however, is that NHS healthcare spending is lower and has been growing more slowly. This means fewer doctors and nurses, and doctors spending less time with patients. The authors vividly suggest that

“Policy makers should consider how recent changes to nursing bursaries, the weakened pound, and uncertainty about the status of immigrant workers in the light of the Brexit referendum result have influenced these numbers and how to respond to these challenges in the future.”

Understandably comparing healthcare systems across the world is difficult. Including the US in the study, and not including other countries like Spain and Japan, may need more justification or could be a scope of future research.

To be fair, the article is a not-to-miss read. It is an eye-opener for those who think it’s only a (too much) demand-side problem the the NHS is facing and confirms the perspective of those who think it’s a (not enough) supply-side problem. Kudos to the hardworking doctors and nurses who are currently delivering efficiently in the stretched situation! For sustainability, the NHS needs to consider increasing its spending to increase labour supply and long-term care.

A systematic review of methods to predict weight trajectories in health economic models of behavioral weight management programs: the potential role of psychosocial factors. Medical Decision Making [PubMed] Published 2nd December 2019

In economic modelling, assumptions are often made about the long-term impact of interventions, and it’s important that these assumptions are based on sound evidence and/or tested in sensitivity analysis, as these could affect the cost-effectiveness results.

The authors explored assumptions about weight trajectories to inform economic modelling of behavioural weight management programmes. Also, they checked their evidence sources, and whether these assumptions were based on any psychosocial variables (such as self-regulation, motivation, self-efficacy, and habit), as these are known to be associated with weight-loss trajectories.

The authors conducted a systematic literature review of economic models of weight management interventions that aimed at reducing weight. In the 38 studies included, they found 6 types of assumptions of weight trajectories beyond trial duration (weight loss maintained, weight loss regained immediately, linear weight regain, subgroup-specific trajectories, exponential decay of effect, maintenance followed by regain), with only 15 of the studies reporting sources for these assumptions. The authors also elaborated on the assumptions and graphically represented them. Psychosocial variables were, in fact, measured in evidence sources of some of the included studies. However, the authors found that none of the studies estimated their weight trajectory assumptions based on these! Though the article also reports on how the assumptions were tested in sensitivity analyses and their impact on results in the studies (if reported within these studies), it would have been interesting to see more insights into this. The authors feel that there’s a need to investigate how psychosocial variables measured in trials can be used within health economic models to calculate weight trajectories and, thus, to improve the validity of cost-effectiveness estimates.

To me, given that only around half of included studies reported sources of assumptions on long-term effects of the interventions and performed sensitivity analysis on these assumptions, it raises the bigger long-debated question on the quality of economic evaluations! To conclude, the review is comprehensive and insightful. It is an interesting read and will be especially useful for those interested in modelling long-term impacts of behavioural support programs.

The societal monetary value of a QALY associated with EQ‐5D‐3L health gains. The European Journal of Health Economics [PubMed] Published 28th November 2019

Finding an estimate of the societal monetary value of a QALY (MVQALY) is mostly performed to inform a range of thresholds for accurately guiding cost-effectiveness decisions.

This study explores the degree of variation in the societal MVQALY based on a large sample of the population in Spain. It uses a discrete choice experiment and a time trade-off exercise to derive a value set for utilities, followed by a willingness to pay questionnaire. The study reveals that the societal values for a QALY, corresponding to different EQ-5D-3L health gains, vary approximately between €10,000 and €30,000. Ironically, the MVQALY associated with larger improvements on QoL was found to be lower than with moderate QoL gains, meaning that WTP is less than proportional to the size of the QoL improvement. The authors further explored whether budgetary restrictions could be a reason for this by analysing responses of individuals with higher income and found out that it may somewhat explain this, but not fully. As this, at face value, implies there should be a lower cost per QALY threshold for interventions with largest improvement of health than with moderate improvements, it raises a lot of questions and forces you to interpret the findings with caution. The authors suggest that the diminishing MVQALY is, at least partly, produced by the lack of sensitivity of WTP responses.

Though I think that the article does not provide a clear take-home message, it makes the readers re-think the very underlying norms of estimating monetary values of QALYs. The study eventually raises more questions than providing answers but could be useful to further explore areas of utility research.

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Alastair Canaway’s journal round-up for 10th June 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.

Analytic considerations in applying a general economic evaluation reference case to gene therapy. Value in Health Published 17th May 2019

For fledgling health economists starting in the world of economic evaluation, the NICE reference case is somewhat of a holy text. If in doubt, check the reference case. The concept of a reference case for economic evaluation has been around since the first US Panel on Cost-Effectiveness in Health and Medicine in 1996 and NICE has routinely used its own reference case for well over a decade. The primary purpose of the reference case is to improve the quality and comparability of economic evaluations by standardising methodological practices. There have been arguments made that the same methods are not appropriate for all medical technologies, particularly those in rare diseases or where no treatment currently exists. The focus of this paper is on gene therapy: a novel method that inserts genetic material into cells (as opposed to a drug/surgery) to treat or prevent disease. In this area there has been significant debate as to the appropriateness of the reference case and whether a new reference case is required in this transformative but expensive area. The purpose of the article was to examine the characteristics of gene therapy and make recommendations on changes to the reference case accordingly.

The paper does an excellent job of unpicking the key components of economic evaluation in relation to gene therapy to examine where weaknesses in current reference cases may lie. Rather than recommend that a new reference case be created, they identify specific areas that should be paid special attention when evaluating gene therapy. Additionally, they produce a three part checklist to help analysts to consider what aspects of their economic evaluation they should consider further. For those about to embark on an economic evaluation of a gene therapy intervention, this paper represents an excellent starting point to guide your methodological choices.

Heterogeneous effects of obesity on mental health: evidence from Mexico. Health Economics [PubMed] [RePEc] Published April 2019

The first line of the ‘summary’ section of this paper caught my eye: “Obesity can spread more easily if it is not perceived negatively”. This stirred up contradictory thoughts. From a public health standpoint we should be doing our utmost to prevent increasing levels of obesity and their related co-morbidities, whilst simultaneously we should be promoting body positivity and well-being for mental health. Is there a tension here? Might promoting body positivity and well-being enable the spread of obesity? This paper doesn’t really answer that question, instead it sought to investigate whether overweight and obesity had differing effects on mental health within different populations groups.

The study is set in Mexico which has the highest rate of obesity in the world with 70% of the population being overweight or obese. Previous research suggests that obesity spreads more easily if not perceived negatively. This paper hypothesises that this effect will be more acute among the poor and middle classes where obesity is more prevalent. The study aimed to reveal the extent of the impact of obesity on well-being whilst controlling for common determinants of well-being by examining the impact of measures of fatness on subjective well-being, allowing for heterogeneous effects across differing groups. The paper focused only on women, who tend to be more affected by excess weight than men (in Mexico at least).

To assess subjective well-being (SWB) the General Health Questionnaire (GHQ) was used whilst weight status was measured using waist to height ratio and additionally an obesity dummy. Data was sourced from the Mexican Family and Life Survey and the baseline sample included over 13,000 women. Various econometric models were employed ranging from OLS to instrumental variable estimations, details of which can be found within the paper.

The results supported the hypothesis. They found that there was a negative effect of fatness on well-being for the rich, whilst there was a positive effect for the poor. This has interesting policy implications: policy attempt to reduce obesity may not work if excess weight is not perceived to be an issue. The findings in this study imply that different policy measures are likely necessary for intervening in the wealthy and the poor in Mexico. The paper offers several explanations as to why this relationship may exist, ranging from the poor having lower returns from healthy time (nod to the Grossman model), to differing labour market penalties from fatness due to different job types for the rich and the poor.

Obviously there are limits to the generalisability of these findings, however it does raise interesting questions about how we should seek to prevent obesity within different elements of society, and the unintended consequences that shifts in attitudes may have.

ICECAP-O, the current state of play: a systematic review of studies reporting the psychometric properties and use of the instrument over the decade since its publication. Quality of Life Research [PubMed] Published June 2019

Those who follow the methodological side of outcome measurement will be familiar with the capability approach, operationalised by the ICECAP suite of measures amongst others. These measures focus on what people are able to do, rather than what they do. It is now 12-13 years since the first ICECAP measure was developed: the ICECAP-O designed for use in older adults. Given the ICECAP measures are now included within the NICE reference case for the economic evaluation of social care, it is a pertinent time to look back over the past decade to assess whether the ICECAP measures are being used and, if so, to what degree and how. This systematic review focusses on the oldest of the ICECAP measures, the ICECAP-O, and examines whether it has been used, and for what purpose as well as summarising the results from psychometric papers.

An appropriate search strategy was deployed within the usual health economic databases, and the PRISMA checklist was used to guide the review. In total 663 papers were identified, of which 51 papers made it through the screening process.

The first 8 years of the ICECAP-O’s life is characterised by an increasing amount of psychometric studies, however in 2014 a reversal occurred. Simultaneously, the number of studies using the ICECAP-O within economic evaluations has slowly increased, surmounting the number examining the psychometric properties, and has increased year-on-year in the three years up to 2018. Overall, the psychometric literature found the ICECAP-O to have good construct validity and generally good content validity with the occasional exception in groups of people with specific medical needs. Although the capability approach has gained prominence, the studies within the review suggest it is still very much seen as a secondary instrument to the EQ-5D and QALY framework, with results typically being brief with little to no discussion or interpretation of the ICECAP-O results.

One of the key limitations to the ICECAP framework to date relates to how economists and decision makers should use the results from the ICECAP instruments. Should capabilities be combined with time (e.g. years in full capability), or should some minimum (sufficient) capability threshold be used? The paper concludes that in the short term, presenting results in terms of ‘years of full capability’ is the best bet, however future research should focus on identifying sufficient capability and establishing monetary thresholds for a year with sufficient capability. Given this, whilst the ICECAP-O has seen increased use over the years, there is still significant work to be done to facilitate decision making and for it to routinely be used as a primary outcome for economic evaluation.

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Alastair Canaway’s journal round-up for 10th July 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.

Use-of-time and health-related quality of life in 10- to 13-year-old children: not all screen time or physical activity minutes are the same. Quality of life Research [PubMedPublished 3rd July 2017

“If you watch too much TV, it’ll make your eyes square” – something I heard a lot as a child. This first paper explores whether this is true (sort of) by examining associations between aspects of time use and HRQL in children aged 10-13 (disclaimer: I peer reviewed it and was pleased to see them incorporate my views). This paper aims to examine how different types of time use are linked to HRQL. Time use was examined by the Multimedia Activity Recall for Children and Adolescents (MARCA) which separates out time into physical activity (sport, active transport, and play), screen time (TV, videogames, computer use), and sleep. The PedsQL was used to assess HRQL, whilst dual x-ray absorptiometry was used to accurately assess fatness. There were a couple of novel aspects to this study, first, the use of absorptiometry to accurately measure body fat percentage rather than the problematic BMI/skin folds in children; second, separating time out into specific components rather than just treating physical activity or screen time as homogeneous components. The primary findings were that for both genders, fatness (negative), sport (positive) and development stage (negative) were associated with HRQL. For boys, the most important other predictor of HRQL was videogames (negative) whilst predictors for girls included television (negative), active transport (negative) and household income (positive). With the exception of ‘active travel’ for girls, I don’t think any of these findings are particularly surprising. As with all cross-sectional studies of this nature, the authors give caution to the results: inability to demonstrate causality. Despite this, it opens the door for various possibilities for future research, and ideas for shaping future interventions in children this age.

Raise the bar, not the threshold value: meeting patient preferences for palliative and end-of-life care. PharmacoEconomics – Open Published 27th June 2017

Health care ≠ end of life care. Whilst health care seeks to maximise health, can the same be said for end of life care? Probably not. This June saw an editorial elaborating on this issue. Health is an important facet of end of life care. However, there are other substantial objects of value in this context e.g. preferences for place of care, preparedness, reducing family burdens etc. Evidence suggests that people at end of life can value these ‘other’ objects more than health status or life extension. Thus there is value beyond that captured by health. This is an issue for the QALY framework where health and length of life are the sole indicators of benefit. The editorial highlights that this is not people wishing for higher cost-per-QALY thresholds at end of life, instead, it is supporting the valuation of key elements of palliative care within the end of life context. It argues that palliative care interventions often are not amenable to integration with survival time in a QALY framework, this effectively implies that end of life care interventions should be evaluated in a separate framework to health care interventions altogether. The editorial discusses the ICECAP-Supportive Care Measure (designed for economic evaluation of end of life measures) as progress within this research context. An issue with this approach is that it doesn’t address allocative efficiency issues (and comparability) with ‘normal’ health care interventions. However, if end of life care is evaluated separately to regular healthcare, it will lead to better decisions within the EoL context. There is merit to this justification, after all, end of life care is often funded via third parties and arguments could, therefore, be made for adopting a separate framework. This, however, is a contentious area with lots of ongoing interest. For balance, it’s probably worth pointing out Chris’s (he did not ask me to put this in!) book chapter which debates many of these issues, specifically in relation to defining objects of value at end of life and whether the QALY should be altogether abandoned at EoL.

Investigating the relationship between costs and outcomes for English mental health providers: a bi-variate multi-level regression analysis. European Journal of Health Economics [PubMedPublished 24th June 2017

Payment systems that incentivise cost control and quality improvements are increasingly used. In England, until recently, mental health services have been funded via block contracts that do not necessarily incentivise cost control and payment has not been linked to outcomes. The National Tariff Payment System for reimbursement has now been introduced to mental health care. This paper harnesses the MHMDS (now called MHSDS) using multi-level bivariate regression to investigate whether it is possible to control costs without negatively affecting outcomes. It does this by examining the relationship between costs and outcomes for mental health providers. Due to the nature of the data, an appropriate instrumental variable was not available, and so it is important to note that the results do not imply causality. The primary results found that after controlling for key variables (demographics, need, social and treatment) there was a minuscule negative correlation between residual costs and outcomes with little evidence of a meaningful relationship. That is, the data suggest that outcome improvements could be made without incurring a lot more cost. This implies that cost-containment efforts by providers should not undermine outcome-improving efforts under the new payment systems. Something to bear in mind when interpreting the results is that there was a rather large list of limitations associated with the analysis, most notably that the analysis was conducted at a provider level. Although it’s continually improving, there still remain issues with the MHMDS data: poor diagnosis coding, missing outcome data, and poor quality of cost data. As somebody who is yet to use MHMDS data, but plans to in the future, this was a useful paper for generating ideas regarding what is possible and the associated limitations.

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