RSS

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

20 May

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.

About these ads
 

Tags: , , , , , , , , , , , , , , , , , , , ,

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

  1. Chris Sampson

    May 20, 2013 at 8:57 am

    Reblogged this on Chris Sampson.

     
  2. Sam Watson

    May 20, 2013 at 9:27 am

    I like the super QALY, although naming it as such may be a little grandiose for many people’s taste! I disagree when you say ‘How we define the equity analysis is incidental’ but I agree that Daniel’s opportunities approach is a good one to pick, particularly since it is independent of utility/welfare and may therefore be a good representative for a measure of equity while the traditional QALY can be our measure of efficiency. This appeals to our notion that equity and efficiency are orthogonal. You could then pick the intervention that had the ‘maximum point’ on a grid with equity on one axis and efficiency on the other. If you picked a measure of equity based on our measure of efficiency it may become more complicated. Just a thought…

     

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

 
Follow

Get every new post delivered to your Inbox.

Join 1,109 other followers

%d bloggers like this: