of QALYs and Quandaries

issues and challenges in the world of health economic evaluation and health technology assessment

A blog about economic evaluation?

Sounds pretty lame. If economics is the dismal science then economic evaluation is its over-achieving cousin—dismal but with an incremental analysis.

Pity me—I’ve been doing this for thirty years, but over that time I’ve worked across a wide range of projects for many different masters. The funny thing is that everyone carries their biases and preconceptions. Sure, pharmaceutical clients want to show their treatment is cost-effective— it’s their job after all. But I’ve yet to meet a clinician in charge of a trial that is in true equipoise. Public health advocates can sometimes be fanatical. And don’t get me started on the crazy machinations some reimbursement agencies go through when appraising products.

Indeed, this is really the reason for this blog. An opportunity to vent and say some of the things I would like to say in scientific articles, but which I can’t get past reviewer 2 without a bunch of supporting references. Seriously, academic publishing is important, but the internet is a huge opportunity to share ideas in a meaningful way. I’ve tried twitter (now X of course), but became disillusioned—partly because it favours heat rather than light—but mainly because of the changes I noticed in myself when using it. So I unplugged and rebooted and instead of joining BlueSky, I find myself here on Substack, looking not for an echo-chamber but for a modern day agora.

So whether you are one of my students, one of my colleagues, or coming from the perspective of government, industry or consultancy, I’m hoping we can get a conversation going around some of the elements of economic evaluation that keep us all occupied and exercised.

I’m aware that it is not advisable to start such an endeavour without a list of topics to feed the beast. So here is my ‘starter of 10’ things that I think could benefit from discussion—a mix of things that just need to be given more attention but also things where the established orthodoxy is misplaced and a fresh look is needed. So (and in no particular order):

• Environmental impact and HTA. A hot topic right now and one I’ve been trying to grapple with. Despite being convinced climate change is the issue of our generation, I’m not convinced that health economic evaluation is the place to be addressing environmental impact?

• Sustainability and HTA. I hear the word sustainability used in many contexts in relation to how HTA should incorporate environmental impacts. But it feels like this word is often used and rarely defined. What does sustainability mean in an HTA context? Something that is at least worth exploring?

• Lifetime time horizons. At the risk of mixing metaphors, insisting on lifetime time horizons for technologies that have to be taken every day and only impact quality of life not mortality, seems like flogging a dead dog(ma). Time to consider when short-term time horizons can and should be relied upon?

• Placebo effects. We are all programmed to think in terms of intention to treat ITT (analysis) but is this the best way to calculate treatment effects for health economic evaluation? I’m not sure.

• Selective attrition and consumer sovereignty. If I need to take a drug everyday for a condition and I stop taking it, does this tell us something about the drugs effectiveness? I would argue it does, and that if people who stop taking drugs are those for who treatment is relatively less effective then this implies the average treatment effect in those that choose to continue taking a treatment is increasing. Should we capture this in our economic evaluation? If we can show selective attrition is real then we would be negligent not to.

• Including productivity gains. I’ve been a big supporter of the ‘Reference Case’ approach to cost-per-QALY analysis over the years. This includes arguing that the Reference Case is justified by the need for comparison and should not stifle innovation. But I worry that innovation is being stifled and that there are situations where productivity gains should at least be part of the conversation.

• Half-cycle corrections. I’ve been teaching a course on modelling methods for economic evaluation for over 20 years now. We don’t teach half-cycle corrections. We try and say they are not important in an incremental analysis. But every year the questions about how to do it come up. Again and again. Perhaps I am mistaken. I will lay out my stall and invite you to convince me that I am wrong.

• Composite endpoints. Widely used in trials but often derided by HTA agencies because of the different values placed on constituent parts. But is this enough to recommend splitting out those components in HTA and if we do, how should we interpret non significant effects?

• Patient engagement. Nothing about us without us. Can we get meaningful patient engagement in health economic modelling? What would that look like? Are there any risks?

• Combination therapies. Effective treatments that are not cost-effective at zero price? We solved that paradox but are HTA agencies doing enough to solve the implementation problem and are patients losing out as a result?

My aim will be to release about one blog post per month. I’ll probably start with environmental impact and HTA as I’m talking on this topic at a conference later this month. But if you, dear reader, have a suggestion then let’s get the conversation started.

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