Chris Sampson’s journal round-up for 22nd May 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 effect of health care expenditure on patient outcomes: evidence from English neonatal care. Health Economics [PubMed] Published 12th May 2017

Recently, people have started trying to identify opportunity cost in the NHS, by assessing the health gains associated with current spending. Studies have thrown up a wide range of values in different clinical areas, including in neonatal care. This study uses individual-level data for infants treated in 32 neonatal intensive care units from 2009-2013, along with the NHS Reference Cost for an intensive care cot day. A model is constructed to assess the impact of changes in expenditure, controlling for a variety of variables available in the National Neonatal Research Database. Two outcomes are considered: the in-hospital mortality rate and morbidity-free survival. The main finding is that a £100 increase in the cost per cot day is associated with a reduction in the mortality rate of 0.36 percentage points. This translates into a marginal cost per infant life saved of around £420,000. Assuming an average life expectancy of 81 years, this equates to a present value cost per life year gained of £15,200. Reductions in the mortality rate are associated with similar increases in morbidity. The estimated cost contradicts a much higher estimate presented in the Claxton et al modern classic on searching for the threshold.

A comparison of four software programs for implementing decision analytic cost-effectiveness models. PharmacoEconomics [PubMed] Published 9th May 2017

Markov models: TreeAge vs Excel vs R vs MATLAB. This paper compares the alternative programs in terms of transparency and validation, the associated learning curve, capability, processing speed and cost. A benchmarking assessment is conducted using a previously published model (originally developed in TreeAge). Excel is rightly identified as the ‘ubiquitous workhorse’ of cost-effectiveness modelling. It’s transparent in theory, but in practice can include cell relations that are difficult to disentangle. TreeAge, on the other hand, includes valuable features to aid model transparency and validation, though the workings of the software itself are not always clear. Being based on programming languages, MATLAB and R may be entirely transparent but challenging to validate. The authors assert that TreeAge is the easiest to learn due to its graphical nature and the availability of training options. Save for complex VBA, Excel is also simple to learn. R and MATLAB are equivalently more difficult to learn, but clearly worth the time saving for anybody expecting to work on multiple complex modelling studies. R and MATLAB both come top in terms of capability, with Excel falling behind due to having fewer statistical facilities. TreeAge has clearly defined capabilities limited to the features that the company chooses to support. MATLAB and R were both able to complete 10,000 simulations in a matter of seconds, while Excel took 15 minutes and TreeAge took over 4 hours. For a value of information analysis requiring 1000 runs, this could translate into 6 months for TreeAge! MATLAB has some advantage over R in processing time that might make its cost ($500 for academics) worthwhile to some. Excel and TreeAge are both identified as particularly useful as educational tools for people getting to grips with the concepts of decision modelling. Though the take-home message for me is that I really need to learn R.

Economic evaluation of factorial randomised controlled trials: challenges, methods and recommendations. Statistics in Medicine [PubMed] Published 3rd May 2017

Factorial trials randomise participants to at least 2 alternative levels (for example, different doses) of at least 2 alternative treatments (possibly in combination). Very little has been written about how economic evaluations ought to be conducted alongside such trials. This study starts by outlining some key challenges for economic evaluation in this context. First, there may be interactions between combined therapies, which might exist for costs and QALYs even if not for the primary clinical endpoint. Second, transformation of the data may not be straightforward, for example, it may not be possible to disaggregate a net benefit estimation with its components using alternative transformations. Third, regression analysis of factorial trials may be tricky for the purpose of constructing CEACs and conducting value of information analysis. Finally, defining the study question may not be simple. The authors simulate a 2×2 factorial trial (0 vs A vs B vs A+B) to demonstrate these challenges. The first analysis compares A and B against placebo separately in what’s known as an ‘at-the-margins’ approach. Both A and B are shown to be cost-effective, with the implication that A+B should be provided. The next analysis uses regression, with interaction terms demonstrating the unlikelihood of being statistically significant for costs or net benefit. ‘Inside-the-table’ analysis is used to separately evaluate the 4 alternative treatments, with an associated loss in statistical power. The findings of this analysis contradict the findings of the at-the-margins analysis. A variety of regression-based analyses is presented, with the discussion focussed on the variability in the estimated standard errors and the implications of this for value of information analysis. The authors then go on to present their conception of the ‘opportunity cost of ignoring interactions’ as a new basis for value of information analysis. A set of 14 recommendations is provided for people conducting economic evaluations alongside factorial trials, which could be used as a bolt-on to CHEERS and CONSORT guidelines.



Thesis Thursday: Raymond Oppong

On the third Thursday of every month, we speak to a recent graduate about their thesis and their studies. This month’s guest is Dr Raymond Oppong who graduated with a PhD from the University if Birmingham. If you would like to suggest a candidate for an upcoming Thesis Thursday, get in touch.

Economic analysis alongside multinational studies
Sue Jowett, Tracy Roberts
Repository link

What attracted you to studying economic evaluation in the context of multinational studies?

One of the first projects that I was involved in when I started work as a health economist was the Genomics to combat Resistance against Antibiotics in Community-acquired lower respiratory tract infections (LRTI) in Europe (GRACE) project. This was an EU-funded study aimed at integrating and coordinating the activities of physicians and scientists from institutions in 14 European countries to combat antibiotic resistance in community-acquired lower respiratory tract infections.

My first task on this project was to undertake a multinational costing study to estimate the costs of treating acute cough/LRTI in Europe. I faced quite a number of challenges including the lack of unit cost data across countries. Conducting a full economic evaluation alongside the interventional studies in GRACE also brought up a number of issues with respect to methods of analysis of multinational trials which needed to be resolved. The desire to understand and resolve some of these issues led me to undertake the PhD to investigate the implications of conducting economic evaluations alongside multinational studies.

Your thesis includes some case studies from a large multinational project. What were the main findings of your empirical work?

I used three main case studies for my empirical work. The first was an observational study aimed at describing the current presentation, investigation, treatment and outcomes of community-acquired lower respiratory tract infections and analysing the determinants of antibiotic use in Europe. The other 2 were RCTs. The first was aimed at studying the effectiveness of antibiotic therapy (amoxicillin) in community-acquired lower respiratory tract infections, whilst the second was aimed at assessing training interventions to improve antibiotic prescribing behaviour by general practitioners. The observational study was used to explore issues relating to costing and outcomes in multinational studies whilst the RCTs explored the various analytical approaches (pooled and split) to economic evaluation alongside multinational studies.

The results from the observational study revealed large variations in costs across Europe and showed that contacting researchers in individual countries was the most effective way of obtaining unit costs. Results from both RCTs showed that the choice of whether to pool or split data had an impact on the cost-effectiveness of the interventions.

What were the key analytical methods used in your analysis?

The overall aim of the thesis was to study the implications of conducting economic analysis alongside multinational studies. Specific objectives include: i) documenting challenges associated with economic evaluations alongside multinational studies, ii) exploring various approaches to obtaining and estimating unit costs, iii) exploring the impact of using different tariffs to value EQ-5D health state descriptions, iv) comparing methods that have been used to conduct economic evaluation alongside multinational studies and v) making recommendations to guide the design and conduct of future economic evaluations carried out alongside multinational studies.

A number of approaches were used to achieve each of the objectives. A systematic review of the literature identified challenges associated with economic evaluations alongside multinational studies. A four-stage approach to obtaining unit costs was assessed. The UK, European and country-specific EQ-5D value sets were compared to determine which is the most appropriate to use in the context of multinational studies. Four analytical approaches – fully pooled one country costing, fully pooled multicountry costing, fully split one country costing and fully split multicountry costing – were compared in terms of resource use, costs, health outcomes and cost-effectiveness. Finally, based on the findings of the study, a set of recommendations were developed.

You completed your PhD part-time while working as a researcher. Did you find this a help or a hindrance to your studies?

I must say that it was both a help and a hindrance. Working in a research environment was really helpful. There was a lot of support from supervisors and colleagues which kept me motivated. I might have not gotten this support if I was not working in a research/academic environment. However, even though some time during the week was allocated to the PhD, I had to completely put it on hold for long periods of time in order to deal with the pressures of work/research. Consequently, I always had to struggle to find my bearings when I got back to the PhD. I also spent most weekends working on the PhD especially when I was nearing submission.

On the whole, it should be noted that a part-time PhD requires a lot of time management skills. I personally had to go on time management courses which were really helpful.

What advice would you give to a health economist conducting an economic evaluation alongside a multinational study?

For a health economist conducting an economic evaluation alongside a multinational trial, it is important to plan ahead and understand the challenges that are associated with economic evaluations alongside multinational studies. A lot of the problems such as those related to the identification of unit costs can be avoided by ensuring adequate measures are put in place at the design stage of the study. An understanding of the various health systems of the countries involved in the study is important in order to make a judgement about the differences and similarities in resource use across countries. Decision makers are interested in results that can be applied to their jurisdiction; therefore it is important to adopt transparent methods e.g. state the countries that participated in the study, state the sources of unit costs and make it clear whether data from all countries (pooling) or from a subset (splitting) were used. To ensure that the results of the study are generalisable to a number of countries it may be advisable to present country-specific results and probably conduct the analysis from different perspectives.

Paul Mitchell’s journal round-up for 15th May 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.

Informal care: choice or constraint. Scandinavian Journal of Caring Sciences [PubMed] Published 12th April 2017

The provision of social care in the UK has become a major economic issue, with recent increases in government spending and local authority taxation to help ease the burden on both the health and social care system in the short term. This study examines some of the issues surrounding informal carers (i.e. care of a family member), estimated to be approximately 10% of the UK population. In particular, it focuses on the role of choice and constraints involved with the decision to become a carer. Using a cross-sectional survey for a UK city, choice of caring was explored in terms of responses to care provision provided, asking if it was a free choice initially to provide care, and if there were constraints in terms of duty, lack of others or financial resources for paid care. The analysis focused on how perceived choice in the caring role was associated with socio-demographics and the type of caring role performed, as well as the role of perceived choice in caring and their wellbeing. Out of the 798 respondents to all four questions on caring choice, about 1 in 3 reported an entirely free choice in the decision, with half reporting having a free choice but also a constraint in terms of duty, other available carers or financial resources. Less than 1 in 5 reported not having a free choice. Only carers with bad health or receiving state benefits had an association with a constrained caring role. The more intense the care role was also associated with a more constrained choice. Higher levels of choice were associated with higher levels of wellbeing across measures of happiness, life satisfaction and capability. In multivariable regression analysis, it was found that having a free choice in the initial caring decision resulted in a higher impact on life satisfaction than educational qualifications and home ownership, whilst improved capability of comparable levels to that of home ownership, all else being equal. The authors thus recommend enhanced choice as a way for policy to improve carers wellbeing. Although the authors acknowledge limitations with the study design being cross-sectional and geographically limited to one city, the study shows there is plenty of scope for understanding the determinants of informal caring and consequences for those carers in much greater detail in future national surveys to help address policy in this area in the medium to longer term.

Experienced utility or decision utility for QALY calculation? Both. Public Health Ethics [PhilPapersPublished 6th May 2017

How health states should be valued in population health metrics, like QALYs and DALYs, will not be an unfamiliar topic of discussion for regular readers of this blog. Instead of arguing for decision utility (i.e. accounting for general population preferences for avoiding health states) or experienced utility (i.e. accounting for patient experiences of health states), the authors in this paper argue for a combined approach, reviving a suggestion previously put forward by Lowenstein & Ubel. The authors neatly summarise some of the issues of relying on either decision utility or experienced utility approaches alone and instead argue for better informed decision utility exercises by using deliberative democracy methods where experienced utility in health states are also presented. Unfortunately, there is little detail of how this process might actually work in practice. There are likely to be issues of what patient experiences are presented in such an exercise and how other biases that may influence decision utility responses are controlled for in such an approach. Although I am generally in favour of more deliberative approaches to elicit informed values for resource allocation, I find that this paper makes a convincing case for neither of the utility approaches to valuation, rather than both.

The value of different aspects of person-centred care: a series of discrete choice experiments in people with long-term conditions. BMJ Open [PubMed] Published 26th April 2017

The term “person-centred care” is one which is gaining some prominence in how healthcare is provided. What it means, and how important different aspects of person-centred care are, is explored in this study using discrete choice experiments (DCEs). Through focus groups and drawing from the authors’ own experience in this area, four aspects of person-centred care for self-management of chronic conditions make up the attributes in the DCE across two levels: (i) information (same information for all/personalised information); (ii) situation (little account of current situation/suggestions that fit current situation); (iii) living well (everyone wants the same from life/works with patient for what they want from life); (iv) communication (neutral professional way/friendly professional way). A cost attribute was also attached to the DCE that was given to patient groups with chronic pain and chronic lung disease. The overall findings suggest that person-centred care focused on situation and living well were valued most with personal communication style valued the least. Latent class analysis also suggested that 1 in 5 of those sampled valued personalised information the most. Those with lower earnings were likely to look to reduce the cost attribute the most. The authors conclude that the focus on communication in current clinician training on person-centred care may not be what is of most value to patients. However, I am not entirely convinced by this argument, as it could be that communication was not seen as an issue by the respondents, perhaps somewhat influenced due to the skills clinicians already have obtained in this area. Clearly, these process aspects of care are difficult to develop attributes for in DCEs, and the authors acknowledge that the wording of the “neutral” and “high” levels may have biased responses. I also found that dropping the “negative” third level for each of the attributes unconvincing. It may have proved more difficult to complete than two levels, but it would have shown in much greater depth how much value is attached to the four attributes relative to one another.