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 of Birmingham. If you would like to suggest a candidate for an upcoming Thesis Thursday, get in touch.

Title
Economic analysis alongside multinational studies
Supervisors
Sue Jowett, Tracy Roberts
Repository link
http://etheses.bham.ac.uk/7288/

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.

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Chris Sampson’s journal round-up for 24th April 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 association between socioeconomic status and adult fast-food consumption in the U.S. Economics & Human Biology Published 19th April 2017

It’s an old stereotype, that people of lower socioeconomic status eat a lot of fast food, and that this contributes to poorer nutritional intake and therefore poorer health. As somebody with a deep affection for Gregg’s pasties and Pot Noodles, I’ve never really bought into the idea. Mainly because a lot of fast food isn’t particularly cheap. And anyway, what about all those cheesy paninis that the middle classes are chowing down on in Starbuck’s? Plus, wouldn’t the more well-off folk have a higher opportunity cost of time that would make fast food more attractive? Happily for me, this paper provides some evidence to support these notions. The study uses 3 recent waves of data from the National Longitudinal Survey of Youth, with 8136 participants born between 1957 and 1964. The authors test for an income gradient in adult fast food consumption, as well as any relationship to wealth. I think that makes it extra interesting because wealth is likely to be more indicative of social class (which is probably what people really think about when it comes to the stereotype). The investigation of wealth also sets it apart from previous studies, which report mixed findings for the income gradient. The number of times people consumed fast food in the preceding 7 days is modelled as a function of price, time requirement, preferences and monetary resources (income and wealth). The models included estimators for these predictors and a number of health behaviour indicators and demographic variables. Logistic models distinguish fast food eaters and OLS and negative binomial models estimate how often fast food is eaten. 79% ate fast food at least once, and 23% were frequent fast food eaters. In short, there isn’t much variation by income and wealth. What there is suggests an inverted U-shape pattern, which is more pronounced when looking at income than wealth. The regression results show that there isn’t much of a relationship between wealth and the number of times a respondent ate fast food. Income is positively related to the number of fast food meals eaten. But other variables were far more important. Living in a central city and being employed were associated with greater fast food consumption, while a tendency to check ingredients was associated with a lower probability of eating fast food. The study has some important policy implications, particularly as our preconceptions may mean that interventions are targeting the wrong groups of people.

Views of the UK general public on important aspects of health not captured by EQ-5D. The Patient [PubMed] Published 13th April 2017

The notion that the EQ-5D might not reflect important aspects of health-related quality of life is a familiar one for those of us working on trial-based analyses. Some of the claims we hear might just be special pleading, but it’s hard to deny at least some truth. What really matters – if we’re trying to elicit societal values – is what the public thinks. This study tries to find out. Face-to-face interviews were conducted in which people completed time trade-off and discrete choice experiment tasks for EQ-5D-5L states. These were followed by a set of questions about the value of alternative upper anchors (e.g. ‘full health’, ‘11111’) and whether respondents believed that relevant health or quality of life domains were missing from the EQ-5D questionnaire. This paper focuses on the aspects of health that people identified as being missing, using a content analysis framework. There were 436 respondents, about half of whom reported being in a 11111 EQ-5D state. 41% of participants considered the EQ-5D questionnaire to be missing some important aspect of health. The authors identified 22 (!) different themes and attached people’s responses to these themes. Sensory deprivation and mental health were the two biggies, with many more responses than other themes. 50 people referred to vision, hearing or other sensory loss. 29 referred to mental health generally while 28 referred to specific mental health problems. This study constitutes a guide for future research and for the development of the EQ-5D and other classification systems. Obviously, the objective of the EQ-5D is not to reflect all domains. And it may be that the public’s suggestions – verbatim, at least – aren’t sensible. 10 people stated ‘cancer’, for example. But the importance of mental health and sensory deprivation in describing the evaluative space does warrant further investigation.

Re-thinking ‘The different perspectives that can be used when eliciting preferences in health’. Health Economics [PubMed] Published 21st March 2017

Pedantry is a virtue when it comes to valuing health states, which is why you’ll often find me banging on about the need for clarity. And why I like this paper. The authors look at a 2003 article by Dolan and co that outlined the different perspectives that health preference researchers ought to be using (though notably aren’t) when presenting elicitation questions to respondents. Dolan and co defined 6 perspectives along two dimensions: preferences (personal, social and socially-inclusive personal) and context (ex ante and ex post). This paper presents the argument that Dolan and co’s framework is incomplete. The authors throw new questions into the mix regarding who the user of treatment is, who the payer is and who is assessing the value, as well as introducing consideration of the timing of illness and the nature of risk. This gives rise to a total of 23 different perspectives along the dimensions of preferences (personal, social, socially-inclusive personal, non-use and proxy) and context (4 ex ante and 1 ex post). This new classification makes important distinctions between different perspectives, and health preference researchers really ought to heed its advice. However, I still think it’s limited. As I described in a recent blog post and discussed at a recent HESG meeting, I think the way we talk about ex ante and ex post in this context is very confused. In fact, this paper demonstrates the problem nicely. The authors first discuss the ex post context, the focus being on the value of ‘treatment’ (an event). Then the paper moves on to the ex ante context, and the discussion relates to ‘illness’ (a state). The problem is that health state valuation exercises aren’t (explicitly) about valuing treatments – or illnesses – but about valuing health states in relation to other health states. ‘Ex ante’ means making judgements about something before an event, and ‘ex post’ means to do so after it. But we’re trying to conduct health state valuation, not health event valuation. May the pedantry continue.

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Chris Sampson’s journal round-up for 3rd April 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.

Return on investment of public health interventions: a systematic review. Journal of Epidemiology & Community Health [PubMed] Published 29th March 2017

Cost-effectiveness analysis in the context of public health is tricky. Often the health benefits are small at the individual level and the returns to investment might be cross-sectoral. Lots of smart people believe that spending on public health is low in proportion to other health spending. Here we have a systematic review of studies reporting cost-benefit ratios (CBR) or return on investment (ROI) estimates for public health interventions. The stated aim of the paper is to demonstrate the false economy associated with cuts to public health spending. 52 titles were included from a search that identified 2957. The inclusion and exclusion criteria are not very clear, with some studies rejected on the basis of ‘poor generalisability to the UK’. There’s a bit too much subjectivity sneaking around in the methods for my liking.  Results for CBR and ROI estimates are presented according to local or national level and grouped by ‘specialism’. From all studies, the median CBR was 8.3 and the median ROI was 14.3. As we might have suspected, public health interventions are cost-saving in a big way. National health protection and legislative interventions offered the greatest return on investment. While there is wide variation in the results, all specialism groupings showed a positive return on average. I don’t doubt the truth of the study’s message – that cuts to public health spending are foolish. But the review doesn’t really demonstrate what the authors want it to demonstrate. We don’t know what (if any) disinvestment is taking place with respect to the interventions identified in the review. The results presented in the study represent a useful reference point for discussion and further analysis, but they aren’t a sufficient basis for supporting general increases in public health spending. That said, the study adds to an already resounding call and may help bring more attention to the issue.

Acceptable health and priority weighting: discussing a reference-level approach using sufficientarian reasoning. Social Science & Medicine Published 27th March 2017

In some ways, the moral principle of sufficiency is very attractive. It acknowledges a desire for redistribution from the haves to the have-nots and may also make for a more manageable goal than all-out maximisation. It may also be particularly useful in specific situations, such as evaluating health care for the elderly, for whom ‘full health’ is never achievable and not a meaningful reference point. This paper presents a discussion of the normative issues at play, drawing insights from the distributive justice literature. We’re reminded of the fair innings argument as a familiar sufficientarian flavoured allocation principle. The sufficientarian approach is outlined in contrast to egalitarianism and prioritarianism. Strict sufficientarian value weighting is not a good idea. If we suppose a socially ‘acceptable’ health state value of 0.7, such an approach would – for example – value an improvement from 0.69 to 0.71 for one person as infinitely more valuable than an improvement from 0.2 to 0.6 for the whole population. The authors go on to outline some more relaxed sufficiency weightings, whereby improvements below the threshold are attributed a value greater than 0 (though still less than those achieving sufficiency). The sufficientarian approach alone is (forgive me) an insufficient framework for the allocation of health care resources and cannot represent the kind of societal preferences that have been observed in the literature. Thus, hybrids are proposed. In particular, a sufficientarian-prioritarian weighting function is presented and the authors suggest that this may be a useful basis for priority setting. One can imagine a very weak form of the sufficientarian approach that corresponds to a prioritarian weighting function that is (perhaps) concave below the threshold and convex above it. Still, we have the major problem of identifying a level of acceptable health that is not arbitrary. The real question you need to ask yourself is this: do you really want health economists to start arguing about another threshold?

Emotions and scope effects in the monetary valuation of health. The European Journal of Health Economics [PubMed] Published 24th March 2017

It seems obvious that emotions could affect the value people attach to goods and services, but little research has been conducted with respect to willingness to pay for health services. This study considers the relationship between a person’s self-reported fear of being operated on and their willingness to pay for risk-reducing drug-eluting stents. A sample of 1479 people in Spain made a series of choices between bare-metal stents at no cost and drug-eluting stents with some out-of-pocket cost, alongside a set of sociodemographic questions and a fear of surgery Likert scale. Each respondent provided 8 responses with 4 different risk reductions and 2 different willingness to pay ‘bids’. The authors outline what they call a ‘cognitive-emotional random utility model’ including an ’emotional shift effect’. Four different models are presented to demonstrate the predictive value of the emotion levels interacting with the risk reduction levels. The sample was split roughly in half according to whether people reported high emotion (8, 9 or 10 on the fear Likert) or low emotion (<8). People who reported more fear of being operated on were willing to pay more for risk reductions, which is the obvious result. More interesting is that the high emotion group exhibited a lower sensitivity to scope – that is, there wasn’t much difference in their valuation of the alternative magnitudes of risk reduction. This constitutes a problem for willingness to pay estimates in this group as it may prevent the elicitation of meaningful values, and it is perhaps another reason why we usually go for collective approaches to health state valuation. The authors conclude that emotional response is a bias that needs to be corrected. I don’t buy this interpretation and would tend to the view that the bias that needs correcting here is that of the economist. Emotions may be a justifiable reflection of personality traits that ought to determine preferences, at least at the individual level. But I do agree with the authors that this is an interesting field for further research if only to understand possible sources of heterogeneity in health state valuation.

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