Alastair Canaway’s journal round-up for 28th November 2016

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 cost-effectiveness of antibiotic prophylaxis for patients at risk of infective endocarditis. Circulation [PubMed] Published 13th November 2016

Did NICE get it wrong? In 2008 NICE recommended stopping antibiotic prophylaxis (AP) for those at risk of infective endocarditis (IE). For those unfamiliar with this research area, AP refers to the use of antibiotics or similar to prevent infection complications. IE is an infection of the endocardial surface of the heart which can have severe, and potentially fatal consequences. NICE stopped the recommendation of AP for those at risk of IE whilst undergoing dental procedures citing lack of evidence of efficacy and cost-effectiveness. This paper sought to fill the void in evidence and conduct an economic evaluation of AP using the latest estimates of efficacy and resource use. The paper constructed a decision analytic model to estimate costs and benefits. Both resource use and adverse event rates were sourced through Hospital Episode Statistics. The results were pretty conclusive: AP was less costly and more effective (than no AP) for all patients at risk of IE. Scenario analyses suggested that AP would have to be substantially less effective than estimated for it to fail on grounds of cost-effectiveness. The paper estimated that the annual savings of reintroducing AP in England would be between £5.5m and £8.2m with a health gain of over 2600 QALYs. Given the low costs of AP, the consequent cost saving and health improvements, perhaps NICE will be persuaded to reconsider their decision.

Maximizing health or sufficient capability in economic evaluation? A methodological experiment of treatment for drug addiction. Medical Decision Making [PubMed] Published 17th November 2016

The standard normative framework for economic evaluation within the UK is extra-welfarism, specifically, using health as the maximand (typically measured using QALYs). Thus, the evaluative space is health, with maximisation as the decision rule. Arguments have been made that health maximisation is not always the most appropriate framework. It has been suggested that the evaluative space be broadened to include capability wellbeing (based on the work of Sen), whilst a minimum threshold approach has been touted as an alternative approach to decision making. Such an approach is egalitarian and aims to ensure all members of society achieve a ‘sufficient’ level of capability wellbeing. This paper reports a pilot trial for the treatment of drug addiction to explore how i) changing the evaluative space to that of capability wellbeing, and ii) switching the decision-making principle to sufficient capability, impacts upon the decisions made. The drug addiction context is particularly pertinent due to non-health spill over impacts to the patient and others. The intervention considers three treatments: treatment as usual (TAU), TAU with social behaviour and network therapy (SBNT) and TAU with goal setting (GS). The two measures of interest within this study are the EQ-5D-5L and the ICECAP-A (capability measure for adults), QALYs and years of full capability (YFC) were calculated. Additionally, years of sufficient capability (YSC) were also calculated, sufficient capability was determined by a score of 33333: ‘a lot’ on each dimension of the ICECAP-A instrument. The study examined four situations: i) broadening the costing perspective from NHS/PSS to government, ii) broadening the evaluative space from QALYs to YFC, iii) broadening both costing perspective and evaluative space, and iv) changing the decision making rule to years of sufficient capability (YSC). The study found that changing from health maximisation to capability maximisation changed the treatment decision, as did changing the perspective: treatment recommendation is sensitive to choice of evaluative space and perspective. In the YSC analysis, the decision remained the same as the YFC analysis. The authors note a number of limitations with their study. The biggest for me, was the sample size of 83 – unsurprising given this was a pilot trial. As a result of the small numbers in each arm (30, 27, and 26) there is a surfeit of uncertainty, and just a handful of extreme cases in any one arm has the potential to change the results, and so it is difficult to draw any firm conclusions from this study. This paper however does provide a good starting point for the novel YFC approach, I’d be very interested in seeing this operationalised in a larger trial.

Does the EQ-5D capture the effects of physical and mental health status on life satisfaction among older people? A path analysis approach. Quality of Life Research [PubMed] Published 19th November 2016

This study sought to identify whether the EQ-5D captures impacts of mental and physical health on life satisfaction (LS) of older adults. This involved a retrospective cohort of 884 patients in Ireland. Path analysis was used to evaluate the direct and indirect effects. The EQ-5D-3L was used to measure health-related quality of life, whilst life satisfaction was measured with the life satisfaction index (LSI). Various specific measures of health status were also measured, e.g. co-morbidity level, activity limitation, and anxiety and depression. Within the analysis a number of assumptions were required, specifically around causation. The overall findings suggest that the EQ-5D-3L sufficiently captures the impact of physical health on life satisfaction, but not mental health. The author’s reflect that this may be due to a fundamental incommensurability of the general public’s preferences (who value the health states for the EQ-5D) and those who experience these health states. The authors conclude that the EQ-5D-3L should be used with caution within economic evaluations, and the use of the EQ-5D will underestimate benefits of treatment to mental health. The authors suggest alternative measures: HUI-3, AQoL and the ICECAP, and advocate their use alongside the EQ-5D within economic evaluation to better capture mental health impacts. A lot of this boils down to existing issues of debate: who should do the valuing (patient vs society), what are we trying to maximise (health vs well-being, or minimum threshold) and are existing measures doing the job they are supposed to be doing (is the EQ-5D fit for purpose). All these are interesting areas and it’s nice to see these issues being pushed to the fore once more.

Credits

The potential of the super QALY to reconcile the key contentions in health economics

Economics is largely about trade-offs and compromise. Academics study the former but don’t often engage in the latter. In health economics, as in other fields, a key trade-off is between equity and efficiency. We’ve been studying this for a.very.long.time. Despite this, as Culyer has identified, equity is hardly considered in current health technology assessments. We all agree it should be, but just can’t seem to figure it out. Indeed, ihas been argued that incorporating equity concerns into cost-effectiveness analyses could still be a long time coming.

But let’s be a bit more positive. The elusive `Super QALY’, as it has been described, should come eventually. And when it does, it’ll be great! One of the reasons, I propose here, is that it has the power to reconcile many of the disagreements that currently fuel (hamper?) debate in our field. Hence, the super QALY might just allow us to get on with fussing over minutia issues of economic evaluation.

Trade-offs

There are necessary trade-offs in decisions of resource allocation. These might be described as the ‘positive’ tensions economists deal with; they relate to decisions that must be made, regardless of our values. The equity–efficiency trade-off is the main one here. But there are others. For example, health care interventions have the dual aim of increasing both the quantity and quality of an individual’s life. The QALY attempts to address this. However, the way we value quality of life also incorporates considerations of length of life in so much as ‘death’ is used in the valuation of health states. This is problematic, as has been discussed. Economists haven’t really gotten round to disagreeing about this yet, but there’s plenty else on which we disagree.

Disagreements

These might be described as ‘normative’ tensions. They concern what different economists think should and should not be done; mainly relating to the process of valuing health states. There are welfarists and non-welfarists. There are those who support societal preferences, and those who support capturing patient experience. It should be clear to most that neither side in these debates is wrong. Most health economists acknowledge the value of capturing utility as well as the importance of capabilities. Most will attach some value to society’s preferences and some to those of the individual.

A super-QALY solution

It’s never been completely clear what the ‘extra’ in extra-welfarism (as currently practiced) actually consists. The super QALY will surely formalise this; it could involve some completely non-welfarist notions. The most common idea of the super QALY is one where the current health-related QALY is weighted based on some equity considerations. So, if this is where economic evaluation is heading, we’re likely to end up with an extra step of estimating the equity impact of an intervention. But, while most studies seem to suggest that this might just be an add-on process, I think it would require a realignment of the methods we already use.

Equity analysis

There’s no need for me to reiterate the importance of equity considerations. Plainly we (economists, the public) care about needs, capabilities, opportunities and equality. How we define the equity analysis is incidental. More important is that we get on with doing it and just see what happens. There are lots of measures we could use and different approaches we could take. For arguments sake (and because I quite like it), let’s say the equity analysis is characterised by a ‘minimum capabilities‘ approach. Something similar to Daniels’s normal opportunity range. People could have the normal opportunity range, have fewer opportunities or have more opportunities. We can argue later about where the threshold lies. People below the threshold could be said to be in ‘need’. Again, argue about this later. States could be defined using a capabilities measure; let’s just say the ICECAP-A for now (though I don’t much like it). Here in the world of health economics we like 0-1 scales, so the ICECAP-A could be valued based on these anchors. So, let’s say 1 is the minimum capabilities or normal opportunity range threshold. Zero equates to being dead. Values can drop below zero where opportunity sets represent a state worse that non-existence. For the equity analysis we are not interested in utility or satisfaction, so the valuation would not be by the individual. Values could be elicited from society, possibly. The valuation technique could be a person trade-off, maybe. Or we could let ethicists come up with weightings. This framework, surely, would satisfy the non-welfarists.

Health utility analysis

I see no reason why the estimation of health benefits cannot be utility-based. Utilitarian satisfaction is sufficient if non-welfarist concerns are incorporated in an equity analysis. Personally I believe that whether this is based on experiences or preferences is largely inconsequential and that, in terms of health, most of the differences demonstrated between the 2 are a function of the elicitation methods. Therefore, utility analysis would remain largely unchanged. However, the value of 0 would change. Zero currently represents either being dead or in a health state equivalent to being dead, despite these two things not being of equivalent value to a person. Under the new framework there is no need to incorporate death into the health utility analysis, as it is accounted for in the equity analysis. 0 should represent the worst health state imaginable. There would be no negative values.

Cost-effectiveness analysis

These 2 analyses would then be combined to form a relatively routine cost-effectiveness analysis to address the efficiency of the intervention. The QALY would be calculated in the usual way, but the ‘Q’ would become ‘super’ by being a function of the 2 different outcomes. Tentatively this could be done by multiplying the two values (alternative formulations could be defined by societal values or by ethicists, depending on your wont). Costings would be carried out in the usual manner and a super ICER could be calculated. Furthermore, the net benefit approach could be implemented in the usual way; possibly with separate willingness-to-pay values for each input to the super QALY (indeed, they may be willingness to pay values from different agents). The table below summarises how the approach might accommodate the various tensions in health economics.

Equity analysis Health utility analysis
Equity Effectiveness
Life Morbidity
Non-welfarism Welfarism
Flourishing Satisfaction
Society The individual

All public policies could be subject to an equity analysis in the way set out above. It is in no way health-specific. Each policy field could then us this to weight their usual outcomes measures – preferably utility-based – to estimate the cost-effectiveness of their intervention. At this point the super QALY makes it onto daytime TV and health economists form a new unelected chamber at the Palace of Westminster.

No doubt this explicitly extra-welfarist approach to the super QALY raises more questions than it is currently able to answer, but we need to get on with trying stuff like this. The super QALY has proven elusive to date but, if we do make it, it may solve a lot of our problems. We may find ourselves having to invent new things to argue about.