Rita Faria’s journal round-up for 13th May 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.

Communicating uncertainty about facts, numbers and science. Royal Society Open Science Published 8th May 2019

This remarkable paper by Anne Marthe van der Bles and colleagues, including the illustrious David Spiegelhalter, covers two of my most favourite topics: communication and uncertainty. They focused on epistemic uncertainty. That is, the uncertainty about facts, numbers and science due to limited knowledge (rather than due to the randomness of the world). This is what we could know more about, if we spent more resources in finding it out.

The authors propose a framework for communicating uncertainty and apply it to two case studies, one in climate change and the other in economic statistics. They also review the literature on the effect of communicating uncertainty. It is so wide-ranging and exhaustive that, if I have any criticism, its 42 pages are not conducive to a leisurely read.

I found the distinction between direct and indirect uncertainty fascinating and incredibly relevant to health economics. Direct uncertainty is about the precision of the evidence whilst indirect uncertainty is about its quality. For example, evidence based on a naïve comparison of patients in a Phase 2 trial with historical controls in another country (yup, this happens!).

So, how should we communicate the uncertainty in our findings? I’m afraid that this paper is not a practical guide but rather a brilliant ground clearing exercise on how to start thinking about this. Nevertheless Box 5 (p35) does give some good advice! I do hope this paper kick-starts research on how to explain uncertainty beyond an academic audience. Looking forward to more!

Was Brexit triggered by the old and unhappy? Or by financial feelings? Journal of Economic Behavior & Organization [RePEc] Published 18th April 2019

Not strictly health economics – although arguably Brexit affects our health – is this impressive study about the factors that contributed to the Leave win in the Brexit referendum. Federica Liberini and colleagues used data from the Understanding Society survey to look at the predictors of people’s views about whether or not the UK should leave the EU. The main results are from a regression on whether or not a person was pro-Brexit, regressed on life satisfaction, their feelings on their financial situation, and other characteristics.

Their conclusions are staggering. They found that people’s views were generally unrelated to their age, their life satisfaction or their income. Instead, it was a person’s feelings about their financial situation that was the strongest predictor. For economists, it may be a bit cringe-worthy to see OLS used for a categorical dependent variable. But to be fair, the authors mention that the results are similar with non-linear models and they report extensive supplementary analyses. Remarkably, they’re making the individual level data available on the 18th of June here.

As the authors discuss, it is not clear if we’re looking at predictive estimates of characteristics related to pro-Brexit feeling or at causal estimates of factors that led to the pro-Brexit feeling. That is, if we could improve someone’s perceived financial situation, would we reduce their probability of feeling pro-Brexit? In any case, the message is clear. Feelings matter!

How does treating chronic hepatitis C affect individuals in need of organ transplants in the United Kingdom? Value in Health Published 8th March 2019

Anupam Bapu Jena and colleagues looked at the spillover benefits of curing hepatitis C given its consequences on the supply and demand of liver and other organs for transplant in the UK. They compare three policies: the status quo, in which there is no screening for hepatitis C and organ donation by people with hepatitis C is rare; universal screen and treat policy where cured people opt-in for organ donation; and similarly, but with opt-out for organ donation.

To do this, they adapted a previously developed queuing model. For the status quo, the model inputs were estimated by calibrating the model outputs to reported NHS performance. They then changed the model inputs to reflect the anticipated impact of the new policies. Importantly, they assumed that all patients with hepatitis C would be cured and no longer require a transplanted organ; conversely, that cured patients would donate organs at similar rates to the general population. They predict that curing hepatitis C would directly reduce the waiting list for organ transplants by reducing the number of patients needing them. Also, there would be an indirect benefit via increasing their availability to other patients. These consequences aren’t typically included in the cost-effectiveness analysis of treatments for hepatitis C, which means that their comparative benefits and costs may not be accurate.

Keeping in the theme of uncertainty, it was disappointing that the paper does not include some sort of confidence bounds on its results nor does it present sensitivity analysis to their assumptions, which in my view, were quite favourable towards a universal screen and test policy. This is an interesting application of a queuing model, which is something I don’t often see in cost-effectiveness analysis. It is also timely and relevant, given the recent drive by the NHS to eliminate hepatitis C. In a few years’ time, we’ll hopefully know to what extent the predicted spillover benefits were realised.


Rita Faria’s journal round-up for 22nd October 2018

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.

Economically efficient hepatitis C virus treatment prioritization improves health outcomes. Medical Decision Making [PubMed] Published 22th August 2018

Hepatitis C treatment was in the news a couple of years ago when the new direct-acting antivirals first appeared on the scene. These drugs are very effective but also incredibly expensive. This prompted a flurry of cost-effectiveness analyses and discussions of the role of affordability in cost-effectiveness (my views here).

This compelling study by Lauren Cipriano and colleagues joins the debate by comparing various strategies to prioritise patients for treatment when the budget is not enough to meet patient demand. This is a clear example of the health losses due to the opportunity cost.

The authors compare the costs and health outcomes of various prioritisation schedules in terms of the number of patients treated, the distribution by severity and age, time to treatment, impact on end-stage liver disease, QALYs, costs and net benefit.

The differences between prioritisation schedules in terms of these various outcomes were remarkable. Reassuringly, the optimal prioritisation schedule on the basis of net benefit (the “optimisation” schedule) was the one that achieved the most QALYs and the greatest net benefit. This was even though the cost-effectiveness threshold did not reflect the opportunity cost, as it was set at $100,000 per QALY gained.

This study is fascinating. It shows how the optimal policy depends on what we are trying to maximise. The “first come first serve” schedule treats the most patients, but it is the “optimisation” schedule that achieves the most health benefits net of the opportunity cost.

Since their purpose was not to compare treatments, the authors used a representative price depending on whether patients had progressed to cirrhosis. A future study could include a comparison between drugs, as our previous work found that there are clear differences in cost-effectiveness between treatment strategies. The more cost-effective the treatment strategies, the more patients can be treated with a given budget.

The authors made the Excel model available as supporting material, together with documentation. This is excellent practice! It disseminates the work and shows openness to independent validation. Well done!

Long-term survival and value of chimeric antigen receptor T-cell therapy for pediatric patients with relapsed or refractory leukemia. JAMA Pediatrics [PubMed] Published 8th October 2018

This fascinating study looks at the cost-effectiveness of tisagenlecleucel in the treatment of children with relapsed or refractory leukaemia compared to chemotherapy.

Tisagenlecleucel is the first chimeric antigen receptor T-cell (CAR-T) therapy. CAR-T therapy is the new kid on the block in cancer treatment. It involves modifying the patient’s own immune system cells to recognise and kill the patient’s cancer (see here for details). Such high-tech treatment comes with a hefty price tag. Tisagenlecleucel is listed at $475,000 for a one-off administration.

The key challenge was to obtain the effectiveness inputs under the chemotherapy option. This was because tisagenlecleucel has only been studied in single-arm trials and individual level data was not available to the research team. The research team selected a single-arm study on the outcomes with clofarabine monotherapy, since its patients at baseline were most similar in terms of demographics and number of prior therapies to the tisagenlecleucel study.

This study is brilliant in approaching a difficult decision problem and conducting extensive sensitivity analysis. In particular, it tests the impact of common drivers of the cost-effectiveness of potentially curative therapies in children, such as the discount rate, duration of benefit, treatment initiation, and the inclusion of future health care costs. Ideally, the sensitivity analysis should also have tested the assumption that the studies informing the effectiveness inputs for tisagenlecleucel and clofarabine monotherapy were comparable or if clofarabine monotherapy does not represent the current standard of care, although it would be difficult to parameterise.

This outstanding study highlights the challenges posed by the approval of treatments based on single-arm studies. Had individual-level data been available, an adjusted comparison may have been possible, which would improve the degree of confidence in the cost-effectiveness of tisagenlecleucel. Regulators and trial sponsors should work together to make anonymised individual level data available to bonafide researchers.

Researcher requests for inappropriate analysis and reporting: a U.S. survey of consulting biostatisticians. Annals of Internal Medicine [PubMed] Published 10th October 2018

This study reports a survey of biostatisticians on the frequency and severity of requests for inappropriate analysis and reporting. The results are stunning!

The top 3 requests in terms of severity were to falsify statistical significance to support a desired result, change data to achieve the desired outcome and remove/alter data records to better support the research hypothesis. Fortunately, this sort of requests appears to be rare.

The top 3 requests in terms of frequency seem to be not showing a plot because it does not show an effect as strong as it had been hoped; to stress only the significant findings but under-reporting non-significant ones, and report results before data have been cleaned and validated.

Given the frequency and severity of the requests, the authors recommend that researchers should be better educated in good statistical practice and research ethics. I couldn’t agree more and would suggest that cost-effectiveness analysis is included, given that it informs policy decisions and it is generally conducted by multidisciplinary teams.

I’m now wondering what the responses would be if we did a similar survey to health economists, particularly those working in health technology assessment! Something for HESG, iHEA or ISPOR to look at for the future?


Chris Sampson’s journal round-up for 5th February 2018

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.

Cost-effectiveness analysis of germ-line BRCA testing in women with breast cancer and cascade testing in family members of mutation carriers. Genetics in Medicine [PubMed] Published 4th January 2018

The idea of testing women for BRCA mutations – faulty genes that can increase the probability and severity of breast and ovarian cancers – periodically makes it into the headlines. That’s not just because of Angelina Jolie. It’s also because it’s a challenging and active area of research with many uncertainties. This new cost-effectiveness analysis evaluates a programme that incorporates cascade testing; testing relatives of mutation carriers. The idea is that this could increase the effectiveness of the programme with a reduced cost-per-identification, as relatives of mutation carriers are more likely to also carry a mutation. The researchers use a cohort-based Markov-style decision analytic model. A programme with three test cohorts – i) women with unilateral breast cancer and a risk prediction score >10%, ii) first-degree relatives, and iii) second-degree relatives – was compared against no testing. A positive result in the original high-risk individual leads to testing in the first- and second-degree relatives, with the number of subsequent tests occurring in the model determined by assumptions about family size. Women who test positive can receive risk-reducing mastectomy and/or bilateral salpingo-oophorectomy (removal of the ovaries). The results are favourable to the BRCA testing programme, at $19,000 (Australian) per QALY for testing affected women only and $15,000 when the cascade testing of family members was included, with high probabilities of cost-effectiveness at $50,000 per QALY. I’m a little confused by the model. The model includes the states ‘BRCA positive’ and ‘Breast cancer’, which clearly are not mutually exclusive. And It isn’t clear how women entering the model with breast cancer go on to enjoy QALY benefits compared to the no-test group. I’m definitely not comfortable with the assumption that there is no disutility associated with risk-reducing surgery. I also can’t see where the cost of identifying the high-risk women in the first place was accounted for. But this is a model, after all. The findings appear to be robust to a variety of sensitivity analyses. Part of the value of testing lies in the information it provides about people beyond the individual patient. Clearly, if we want to evaluate the true value of testing then this needs to be taken into account.

Economic evaluation of direct-acting antivirals for hepatitis C in Norway. PharmacoEconomics Published 2nd February 2018

Direct-acting antivirals (DAAs) are those new drugs that gave NICE a headache a few years back because they were – despite being very effective and high-value – unaffordable. DAAs are essentially curative, which means that they can reduce resource use over a long time horizon. This makes cost-effectiveness analysis in this context challenging. In this new study, the authors conduct an economic evaluation of DAAs compared with the previous class of treatment, in the Norwegian context. Importantly, the researchers sought to take into account the rebates that have been agreed in Norway, which mean that the prices are effectively reduced by up to 50%. There are now lots of different DAAs available. Furthermore, hepatitis C infection corresponds to several different genotypes. This means that there is a need to identify which treatments are most (cost-)effective for which groups of patients; this isn’t simply a matter of A vs B. The authors use a previously developed model that incorporates projections of the disease up to 2030, though the authors extrapolate to a 100-year time horizon. The paper presents cost-effectiveness acceptability frontiers for each of genotypes 1, 2, and 3, clearly demonstrating which medicines are the most likely to be cost-effective at given willingness-to-pay thresholds. For all three genotypes, at least one of the DAA options is most likely to be cost-effective above a threshold of €70,000 per QALY (which is apparently recommended in Norway). The model predicts that if everyone received the most cost-effective strategy then Norway would expect to see around 180 hepatitis C patients in 2030 instead of the 300-400 seen in the last six years. The study also presents the price rebates that would be necessary to make currently sub-optimal medicines cost-effective. The model isn’t that generalisable. It’s very much Norway-specific as it reflects the country’s treatment guidelines. It also only looks at people who inject drugs – a sub-population whose importance can vary a lot from one country to the next. I expect this will be a valuable piece of work for Norway, but it strikes me as odd that “affordability” or “budget impact” aren’t even mentioned in the paper.

Cost-effectiveness of prostate cancer screening: a systematic review of decision-analytical models. BMC Cancer [PubMed] Published 18th January 2018

You may have seen prostate cancer in the headlines last week. Despite the number of people in the UK dying each year from prostate cancer now being greater than the number of people dying from breast cancer, prostate cancer screening remains controversial. This is because over-detection and over-treatment are common and harmful. Plenty of cost-effectiveness studies have been conducted in the context of detecting and treating prostate cancer. But there are various ways of modelling the problem and various specifications of screening programme that can be evaluated. So here we have a systematic review of cost-effectiveness models evaluating prostate-specific antigen (PSA) blood tests as a basis for screening. From a haul of 1010 studies, 10 made it into the review. The studies modelled lots of different scenarios, with alternative screening strategies, PSA thresholds, and treatment pathways. The results are not consistent. Many of the scenarios evaluated in the studies were more costly and less effective than current practice (which tended to be the lack of any formal screening programme). None of the UK-based cost-per-QALY estimates favoured screening. The authors summarise the methodological choices made in each study and consider the extent to which this relates to the pathways being modelled. They also specify the health state utility values used in the models. This will be a very useful reference point for anyone trying their hand at a prostate cancer screening model. Of the ten studies included in the review, four of them found at least one screening programme to be potentially cost-effective. ‘Adaptive screening’ – whereby individuals’ recall to screening was based on their risk – was considered in two studies using patient-level simulations. The authors suggest that cohort-level modelling could be sufficient where screening is not determined by individual risk level. There are also warnings against inappropriate definition of the comparator, which is likely to be opportunistic screening rather than a complete absence of screening. Generally speaking, a lack of good data seems to be part of the explanation for the inconsistency in the findings. It could be some time before we have a clearer understanding of how to implement a cost-effective screening programme for prostate cancer.