Thesis Thursday: Francesco Longo

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 Francesco Longo who has a PhD from the University of York. If you would like to suggest a candidate for an upcoming Thesis Thursday, get in touch.

Essays on hospital performance in England
Luigi Siciliani
Repository link

What do you mean by ‘hospital performance’, and how is it measured?

The concept of performance in the healthcare sector covers a number of dimensions including responsiveness, affordability, accessibility, quality, and efficiency. A PhD does not normally provide enough time to investigate all these aspects and, hence, my thesis mostly focuses on quality and efficiency in the hospital sector. The concept of quality or efficiency of a hospital is also surprisingly broad and, as a consequence, perfect quality and efficiency measures do not exist. For example, mortality and readmissions are good clinical quality measures but the majority of hospital patients do not die and are not readmitted. How well does the hospital treat these patients? Similarly for efficiency: knowing that a hospital is more efficient because it now has lower costs is essential, but how is that hospital actually reducing costs? My thesis tries to answer also these questions by analysing various quality and efficiency indicators. For example, Chapter 3 uses quality measures such as overall and condition-specific mortality, overall readmissions, and patient-reported outcomes for hip replacement. It also uses efficiency indicators such as bed occupancy, cancelled elective operations, and cost indexes. Chapter 4 analyses additional efficiency indicators, such as admissions per bed, the proportion of day cases, and proportion of untouched meals.

You dedicated a lot of effort to comparing specialist and general hospitals. Why is this important?

The first part of my thesis focuses on specialisation, i.e. an organisational form which is supposed to generate greater efficiency, quality, and responsiveness but not necessarily lower costs. Some evidence from the US suggests that orthopaedic and surgical hospitals had 20 percent higher inpatient costs because of, for example, higher staffing levels and better quality of care. In the English NHS, specialist hospitals play an important role because they deliver high proportions of specialised services, commonly low-volume but high-cost treatments for patients with complex and rare conditions. Specialist hospitals, therefore, allow the achievement of a critical mass of clinical expertise to ensure patients receive specialised treatments that produce better health outcomes. More precisely, my thesis focuses on specialist orthopaedic hospitals which, for instance, provide 90% of bone and soft tissue sarcomas surgeries, and 50% of scoliosis treatments. It is therefore important to investigate the financial viability of specialist orthopaedic hospitals relative to general hospitals that undertake similar activities, under the current payment system. The thesis implements weighted least square regressions to compare profit margins between specialist and general hospitals. Specialist orthopaedic hospitals are found to have lower profit margins, which are explained by patient characteristics such as age and severity. This means that, under the current payment system, providers that generally attract more complex patients such as specialist orthopaedic hospitals may be financially disadvantaged.

In what way is your analysis of competition in the NHS distinct from that of previous studies?

The second part of my thesis investigates the effect of competition on quality and efficiency under two different perspectives. First, it explores whether under competitive pressures neighbouring hospitals strategically interact in quality and efficiency, i.e. whether a hospital’s quality and efficiency respond to neighbouring hospitals’ quality and efficiency. Previous studies on English hospitals analyse strategic interactions only in quality and they employ cross-sectional spatial econometric models. Instead, my thesis uses panel spatial econometric models and a cross-sectional IV model in order to make causal statements about the existence of strategic interactions among rival hospitals. Second, the thesis examines the direct effect of hospital competition on efficiency. The previous empirical literature has studied this topic by focusing on two measures of efficiency such as unit costs and length of stay measured at the aggregate level or for a specific procedure (hip and knee replacement). My thesis provides a richer analysis by examining a wider range of efficiency dimensions. It combines a difference-in-difference strategy, commonly used in the literature, with Seemingly Unrelated Regression models to estimate the effect of competition on efficiency and enhance the precision of the estimates. Moreover, the thesis tests whether the effect of competition varies for more or less efficient hospitals using an unconditional quantile regression approach.

Where should researchers turn next to help policymakers understand hospital performance?

Hospitals are complex organisations and the idea of performance within this context is multifaceted. Even when we focus on a single performance dimension such as quality or efficiency, it is difficult to identify a measure that could work as a comprehensive proxy. It is therefore important to decompose as much as possible the analysis by exploring indicators capturing complementary aspects of the performance dimension of interest. This practice is likely to generate findings that are readily interpretable by policymakers. For instance, some results from my thesis suggest that hospital competition improves efficiency by reducing admissions per bed. Such an effect is driven by a reduction in the number of beds rather than an increase in the number of admissions. In addition, competition improves efficiency by pushing hospitals to increase the proportion of day cases. These findings may help to explain why other studies in the literature find that competition decreases length of stay: hospitals may replace elective patients, who occupy hospital beds for one or more nights, with day case patients, who are instead likely to be discharged the same day of admission.

Thesis Thursday: a guide to sources

Despite our best efforts, we’ve ended up without a guest for Thesis Thursday this month. Rather than try and let the January 2018 edition slide by unnoticed, I thought I should take the opportunity to write something a bit different on the subject.

The premise for Thesis Thursday is that there’s lots of exciting research going on around the world by early career researchers as part of doctoral programmes. One of the reasons we think Thesis Thursday is useful (as well as providing insight into the lives of health economics PhD students) is that it exposes readers to research that they might not otherwise get to see until after a long drawn-out publication process or, worse, that might never see the light of day at all.

In this blog post I’ll provide some insight into how we find candidates for Thesis Thursday and how you – between instalments – can get your thesis fix. Or, more likely, how you might be able to use PhD theses more in your research.

The big databases

There are some major repositories around the world for doctoral theses. If you’re looking for a thesis from a British university then your first stop should be EThOS, hosted by the British Library. The search function will be familiar to anyone who has used a bibliographic database. You can also limit your searches by award year and whether or not the thesis is available for immediate download (more on this in a moment).

A good resource for North American theses (and dissertations) is ProQuest, though it’s unfortunately only available to those with a subscription – institutional or otherwise. There is a health economics subject page with a weak collection of 72 theses (none more recent than 2012). But if you dig deeper using search terms you will find a wealth of PhD outputs from universities you’ve never even heard of. The quality is variable, but there are some excellent pieces of work buried in here. We’ll be trying to publicise them using Thesis Thursday.

There are plenty of other databases that bring together theses from multiple sources; these are simply the databases that I use. Honourable mentions also go to Open Access Theses and Dissertations and the NDLTD archive, which seem to have a better international reach than many others.

Institutional repositories

Most universities have their own internal thesis repositories. Most British universities use the standard EPrints system, so their use is familiar. While I’m reluctant to reinforce the Sheffield-York axis of power, the White Rose thesis repository is particularly useful for health economics theses. It’s a doddle to find the latest theses from ScHARR, CHE, and AUHE, though I’m not entirely convinced that they have complete coverage. Further afield in Europe, Erasmus has a good repository of health economics theses. Or, if you’ve been practising your Dutch, you can find a larger repository that includes the likes of Tilburg and Groningen.

Most theses in institutional repositories are embargoed. This means that it isn’t possible to download the thesis unless you make a special request and are granted permission. These theses aren’t likely to be chosen to be featured on the blog because they pose the additional challenge of trying to get sight of the work itself. I wish everybody would make their thesis freely accessible…

A call for candidates

Today’s Thesis Thursday didn’t happen because we weren’t able to find a guest who felt able to contribute. Recent graduates can be hard to track down. Email addresses stop working and subsequent affiliations (if any) are not always clear. If you would like to feature in an upcoming Thesis Thursday or you’d like to recommend someone, get in touch. We shan’t hold it against you if your thesis is not available online, but please be ready with your PDF!


Thesis Thursday: Caroline Vass

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 Caroline Vass who has a PhD from the University of Manchester. If you would like to suggest a candidate for an upcoming Thesis Thursday, get in touch.

Using discrete choice experiments to value benefits and risks in primary care
Katherine Payne, Stephen Campbell, Daniel Rigby
Repository link

Are there particular challenges associated with asking people to trade-off risks in a discrete choice experiment?

The challenge of communicating risk in general, not just in DCEs, was one of the things which drew me to the PhD. I’d heard a TED talk discussing a study which asked people’s understanding of weather forecasts. Although most people think they understand a simple statement like “there’s a 30% chance of rain tomorrow”, few people correctly interpreted that as meaning it will rain 30% of the days like tomorrow. Most interpret it to mean there will be rain 30% of the time or in 30% of the area.

My first ever publication was reviewing the risk communication literature, which confirmed our suspicions; even highly educated samples don’t always interpret information as we expect. Therefore, testing if the communication of risk mattered when making trade-offs in a DCE seemed a pretty important topic and formed the overarching research question of my PhD.

Most of your study used data relating to breast cancer screening. What made this a good context in which to explore your research questions?

All women are invited to participate in breast screening (either from a GP referral or at 47-50 years old) in the UK. This makes every woman a potential consumer and a potential ‘patient’. I conducted a lot of qualitative research to ensure the survey text was easily interpretable, and having a disease which many people had heard of made this easier and allowed us to focus on the risk communication formats. My supervisor Prof. Katherine Payne had also been working on a large evaluation of stratified screening which made contacting experts, patients and charities easier.

There are also national screening participation figures so we were able to test if the DCE had any real-world predictive value. Luckily, our estimates weren’t too far off the published uptake rates for the UK!

How did you come to use eye-tracking as a research method, and were there any difficulties in employing a method not widely used in our field?

I have to credit my supervisor Prof. Dan Rigby with planting the seed and introducing me to the method. I did a bit of reading into what psychologists thought you could measure using eye-movements and thought it was worth further investigation. I literally found people publishing with the technology at our institution and knocked on doors until someone would let me use it! If the University of Manchester didn’t already have the equipment, it would have been much more challenging to collect these data.

I then discovered the joys of lab-based work which I think many health economists, fortunately, don’t encounter in their PhDs. The shared bench, people messing with your experiment set-up, restricted lab time which needs to be booked weeks in advance etc. I’m sure it will all be worth it… when the paper is finally published.

What are the key messages from your research in terms of how we ought to be designing DCEs in this context?

I had a bit of a null-result on the risk communication formats, where I found it didn’t affect preferences. I think looking back that might have been with the types of numbers I was presenting (5%, 10%, 20% are easier to understand) and maybe people have a lot of knowledge about the risks of breast screening. It certainly warrants further research to see if my finding holds in other settings. There is a lot of support for visual risk communication formats like icon arrays in other literatures and their addition didn’t seem to do any harm.

Some of the most interesting results came from the think-aloud interviews I conducted with female members of the public. Although I originally wanted to focus on their interpretation of the risk attributes, people started verbalising all sorts of interesting behaviour and strategies. Some of it aligned with economic concepts I hadn’t thought of such as feelings of regret associated with opting-out and discounting both the costs and health benefits of later screens in the programme. But there were also some glaring violations, like ignoring certain attributes, associating cost with quality, using other people’s budget constraints to make choices, and trying to game the survey with protest responses. So perhaps people designing DCEs for benefit-risk trade-offs specifically or in healthcare more generally should be aware that respondents can and do adopt simplifying heuristics. Is this evidence of the benefits of qualitative research in this context? I make that argument here.

Your thesis describes a wealth of research methods and findings, but is there anything that you wish you could have done that you weren’t able to do?

Achieved a larger sample size for my eye-tracking study!